Dana Farber Webchat: The Latest in Ovarian Cancer Treatment & Research

The latest developments in ovarian cancer treatment and research are addressed in the video below via a Dana-Farber Cancer Institute webchat that was conducted on September 16, 2014.

The Susan F. Smith Center for Women’s Cancers at the Dana-Farber Cancer Institute conducted a live video webchat panel with Ursula Matulonis, M.D., medical director of the Gynecologic Oncology Program, and gynecologic oncologists Panos Konstantinopoulos, M.D., Ph.D., and Susana Campos, M.D., MPH. The live webchat was held on September 16, 2014.

The general webchat topics addressed by the Dana-Farber doctors are listed below. For your convenience, we also provided the approximate video start time associated with each discussion topic. The entire video runs 49 minutes and 20 seconds.

  • Various types/subtypes of ovarian cancer and treatment differences. [1:40 minutes]
  • CA-125 and other ovarian cancer biomarkers. [5:10 minutes]
  • Areas of ongoing ovarian cancer research. [9:28 minutes]
  • Ovarian cancer treatment alternatives to standard of care chemotherapy. [13:55 minutes]
  • PARP Inhibitors & Immunotherapy. [15:03 minutes]
  • Mechanisms to reverse platinum drug resistance. [17:15 minutes]
  • Correlation between ovarian cancer and HPV (Human papillomavirus). [19:30 minutes]
  • The use of clinical trials for the treatment of ovarian cancer. [19:43 minutes]
  • Stage 1 ovarian cancer prognosis. [21:47 minutes]
  • Gene mutations related to hereditary ovarian cancer risk. [22:55 minutes]
  • Treatment options for platinum drug refractory/resistant ovarian cancer. [25:27 minutes]
  • Treatment of BRCA gene-mutated ovarian cancer patients. [27:50 minutes]
  • Ovarian cancer prevention. [30:18 minutes]
  • Promising treatments for ovarian clear cell cancer. [31:43 minutes]
  • Proper nutrition during and after ovarian cancer treatment. [33:47 minutes]
  • Symptoms associated with an ovarian cancer recurrence. [35:06 minutes]
  • Ovarian neuroendocrine cancer. [36:16 minutes]
  • Small-cell ovarian cancer. [39:22 minutes]
  • Origin of ovarian cancer. [42:41 minutes]
  • Treatment options for isolated or limited recurrent ovarian cancer tumors/lesions. [45:26 minutes]
  • Closing: Most Exciting Ovarian Cancer Developments. [47:07 minutes]

 

U.K. Researchers Launch Clinical Trial of Mercaptopurine (6-MP) In Women with Hereditary Breast and Ovarian Cancer

A Cancer Research UK-funded clinical trial of a new drug for patients with advanced breast or ovarian cancer due to inherited BRCA gene mutations has been launched at the Experimental Cancer Medicine Centre at the University of Oxford.

A Cancer Research UK-funded trial of a new drug for patients with advanced breast or ovarian cancer due to inherited BRCA gene faults has been launched at the Experimental Cancer Medicine Centre at the University of Oxford (OxFord ECMC).

Mutations in the BRCA 1 (BReast CAncer-1) and BRCA 2 genes are thought to account for around 2-5 percent of all breast cancer cases. Women carrying the BRCA1 and BRCA2 mutation have a 45-65 percent chance of developing breast cancer, and a 20-45 percent chance of developing ovarian cancer, by the age of 70. Genetic testing for faulty BRCA genes is available for women with a very strong family history.

DNA damage, due to environmental factors and normal metabolic processes inside the cell, occurs at a rate of 1,000 to 1,000,000 molecular lesions per cell per day. A special enzyme (shown above in color), encircles the double helix to repair a broken strand of DNA. Without molecules that can mend DNA single strand and double strand breaks, cells can malfunction, die, or become cancerous. (Photo: Courtesy of Tom Ellenberger, Washington University School of Medicine in St. Louis)

Cells lacking a properly functioning BRCA1 or BRCA2 gene  are less able to repair DNA damage. These defective cells are more sensitive to (i) platinum-based chemotherapy drugs such as cisplatin – which work by causing double-stranded DNA breaks, and (ii) PARP inhibitors, a newer class of drugs which prevent cells lacking a properly functioning BRCA gene from being able to repair damaged DNA. PARP inhibitors have shown promise in clinical trials but, as with most drugs, resistance can develop meaning some women can stop responding.

This trial, led by a team based at the National Institute for Health Research (NIHR) Oxford Biomedical Research Centre, is looking at a drug called “6MP” (a/k/a mercaptopurine; brand name: Purinethol), which is already used to treat leukemia and is often given in combination with another chemotherapy drug called “methotrexate.”

Earlier studies involving cells grown in the laboratory suggest that a class of drugs called “thiopurines,” which includes 6MP, are effective at killing cancer cells lacking BRCA – a gene which significantly increases the risk of breast and ovarian cancer – even after they have developed resistance to treatments like PARP inhibitors and cisplatin.

This trial is one of a growing number looking at matching patients to the most appropriate treatment based on their genetic makeup and that of their cancer – an approach known as “personalized medicine.”

If successful, the results will pave the way for a larger Phase 3 clinical trial, which could lead to an additional treatment option for the 15 out of every 100 women with breast and ovarian cancers, which are caused by faults in the BRCA1 or BRCA2 gene.

Trial leader Dr. Shibani Nicum, a gynecology specialist based at the Oxford ECMC, and a researcher in Oxford University’s Department of Oncology, said: “PARP inhibitors are a powerful new class of drugs developed specifically to target tumors caused by BRCA 1 and BRCA2 faults, but drug resistance remains a problem. We hope that the very encouraging results we have seen in early laboratory studies involving 6MP will lead to increased treatment options for these patients in the future.”

U.K. trial participant Suzanne Cole, 54, from Newbury, has a strong history of ovarian cancer in her family, with her sister, mother and grandmother all having been diagnosed with suspected cases of the disease at a relatively young age. But, it was not until many years later, after she herself was diagnosed with cancer, that doctors were able to trace the cause of this back to a BRCA1 mutation in her family.

Suzanne Cole said: “I was diagnosed in 2009 and initially had surgery then chemotherapy. I was then told about the trial and I went away and studied the information. The doctors were able to answer all my questions and then I agreed to sign up. I’m happy to be a part of this work as it could help others by moving treatments forward.”

Professor Mark Middleton, director of the Oxford ECMC, said: “It’s exciting to see drugs being developed for specific groups of patients who share the same underlying genetic faults in their cancer. Targeted treatments are at the cutting edge of cancer care and we’re proud to be involved in bringing such drugs a step closer to the clinic.”

Dr. Sally Burtles, Cancer Research UK’s director of the ECMC Network, said: “This study helps demonstrate the value of being able to pool subsets of patients who share specific rare faults in their tumor from a UK-wide network of Experimental Cancer Medicine Centres. This will be crucial as we move towards a new era of personalized medicine with treatments targeted according to the individual biological profile of a patient’s cancer.”

For more information on the trial, please visit www.cancerhelp.org.uk, or call the Cancer Research UK cancer information nurses on 0808-800-4040.

Sources:

  • Researchers trial new drug for women with hereditary breast and ovarian cancer, Press Release, Cancer Research UK, August 17, 2011.
  • Issaeva N, et al. 6-thioguanine selectively kills BRCA2-defective tumors and overcomes PARP inhibitor resistance. Cancer Res. 2010 Aug 1;70(15):6268-76. Epub 2010 Jul 14. PubMed PMID: 20631063; PubMed PMCID: PMC2913123.

2011 ASCO: Exelixis Reports Expanded Cabozantinib (XL184) Phase II Data For Advanced Ovarian Cancer; Six Deaths Reported

Exelixis, Inc. reported expanded Phase 2 study data with respect to cabozantinib (XL184) use in advanced ovarian cancer patients at the recent 2011 American Society of Clinical Oncology Annual Meeting. The overall solid tumor Phase 2 safety and tolerability data reference six deaths, including two ovarian cancer patients.

Ronald J. Buckanovich, M.D., Ph.D., Assistant Professor, Departments of Internal Medicine & Obstetrics and Gynecology, University of Michigan

Exelixis, Inc. reported expanded Phase 2 study data with respect to cabozantinib (XL184) use in advanced ovarian cancer patients at the 2011 American Society of Clinical Oncology (ASCO) Annual Meeting . The overall solid tumor Phase 2 safety and tolerability data refers to six deaths, including two ovarian cancer patients.

On May 19, 2011, we reported promising cabozantinib phase 2 solid tumor (including ovarian) data, which was presented at an ASCO press briefing held in advance of the 2011 ASCO Annual Meeting. As noted in our May 19 article, cabozantinib demonstrated excellent activity against several solid tumors, including ovarian cancer. In addition, we reported that cabozantinib showed promising activity in ovarian cancer patients independent of prior response to platinum drug-based therapies.

Ronald J. Buckanovich, M.D., Ph.D., Assistant Professor, Departments of Internal Medicine & Obstetrics and Gynecology, University of Michigan, presented the expanded cabozantinib Phase 2 data relating to use of the drug in advanced ovarian cancer patients, on June 4 at the 2011 ASCO Annual Meeting.

Ovarian Cancer Patient Population & Overall Response Rate

(Image Source: Exelixis, Inc.)

The cabozantinib trial is an ongoing phase 2 adaptive randomized discontinuation trial. As of the February 11, 2011 cut-off date, accrual in the cabozantinib study cohort was complete at 70 patients.

The 70 patients enrolled in the ovarian cancer cohort received oral cabozantinib (100 mg) daily over a 12 week “Lead-in Stage.” These patients had a minimum follow-up of at least 12 weeks and were thus evaluable for safety and the primary efficacy endpoint of response per RECIST (Response Evaluation Criteria in Solid Tumors).

Patient tumor response was assessed every 6 weeks. Receipt of cabozantinib treatment beyond the 12 week open label Lead-in Stage was based upon patient response: (1) patients with a partial response (PR) or complete response (CR) continued taking cabozantinib, (2) patients with stable disease (SD) were randomized to the cabozantinib treatment arm or the placebo treatment arm (collectively referred to as the “Blinded Randomized Stage”), and (iii) patients with progressive disease (PD) discontinued study treatment. The study primary endpoint was overall response rate (ORR) per RECIST in the Lead-in Stage, and progression free survival (PFS) in the Blinded Randomized Stage. Accrual in any cohort could be halted for high ORR or PD.

Approximately half of the 70 patients enrolled in the cohort were considered platinum drug-refractory/-resistant (49%), defined as a platinum drug-free interval of 6 months or less, and the remainder of patients (51%) had platinum-sensitive disease based on a platinum-free interval greater than 6 months.

The baseline patient tumor histologic characteristics are as follows: serous ovarian cancer (79%), clear cell ovarian cancer (4%), endometrioid ovarian cancer (6%), and other forms of ovarian cancer (11%)

More than half the patients (57%) received 2 or more prior lines of platinum therapy prior to trial enrollment. Some patients also had additional prior lines of therapy with agents such as pegylated liposomal doxorubicin (brand name: Doxil®) or topotecan (brand name: Hycamtin®) (32%), gemcitabine (brand name: Gemzar®) (29%), and VEGF (vascular endothelial growth factor) pathway inhibitors (10%).

Evidence of objective tumor regression was observed in 73% of patients with at least 1 post-baseline medical imaging scan. The best overall response rate per RECIST criteria was 24% (16 PRs and 1 CR). The overall Week-12 disease control rate (DRC = CR + PR + SD) was 53%. The Week-12 DCRs in the platinum drug-refractory, -resistant, and -sensitive groups were 36%, 39%, and 67%, respectively.

Based on an observed high rate of clinical activity, randomization was halted, and randomized patients were unblinded.  At this point, the unblinded randomized patients that were treated with placebo were allowed to “cross-over” to treatment with cabozantinib. Disease stabilization was experienced by some ovarian cancer patients who had progressive disease prior to treatment cross-over.

“These latest results in metastatic ovarian cancer demonstrate the potential broad utility of cabozantinib beyond bone-predominant types of cancers such as castration-resistant prostate cancer. The high rates of durable response with our dual inhibitor of MET and VEGFR2 compare favorably to those of other single-agent targeted therapies and cytotoxic agents in development,” said Michael M. Morrissey, Ph.D., president and chief executive officer of Exelixis. “These results underscore the potential of cabozantinib in metastatic ovarian cancer, and we are in discussions with leading cooperative groups to plan further evaluation of cabozantinib in randomized trials for this indication.”

Activity in Platinum Drug-Sensitive, -Refractory, and -Resistant Disease

Ignace Vergote, M.D., Ph.D., senior author of the cabozantinib (XL184) ASCO presentation & Chairman, Leuven Cancer Institute, University of Leuven, European Union

(Image Source: Exelixis, Inc.)

Two of 11 patients (18%) with platinum refractory disease, defined as a platinum-free interval of <1 month, achieved a confirmed response (1 CR and 1 PR).

In the subset of patients with platinum-resistant disease, defined as a platinum-free interval of 1-6 months, 5 of 23 (22%) achieved a PR.

Ten of 36 patients (28%) with platinum sensitive disease achieved a PR.

A total of 37 patients experienced reductions in the ovarian cancer tumor marker CA-125 (cancer antigen-125), including 8 with decreases greater than 50%. There is no consistent concordance between CA-125 changes and tumor regression. The median duration of response has not yet been reached with 36 weeks of median follow-up.

“The continued activity of cabozantinib in a larger population of ovarian cancer patients is very encouraging, especially with respect to the clinical benefit observed in both platinum-sensitive and platinum-resistant/refractory disease. This activity profile has not been observed with other single-agent TKIs [tyrosine kinase inhibitors], and cabozantinib has the potential to be an important new treatment for ovarian cancer,” said Ignace Vergote, M.D., Ph.D., senior author of the presentation and Chairman of the Leuven Cancer Institute at the University of Leuven, European Union. “The high rate of disease control in platinum-resistant and platinum-refractory disease suggests that cabozantinib may help to address the substantial unmet medical need faced by patients who have sub-optimal responses to platinum-based therapies. I believe that further evaluation will help to define the potential role of cabozantinib in the treatment of ovarian cancer.”

General Safety & Tolerability Data 

Safety data are available for the 70 patients in the Lead-In phase of the cabozantinib study. The most common CTCAE (Common Terminology Criteria for Adverse Eventsgrade 3 or 4 adverse events (AEs), regardless of causality, were diarrhea (10%), fatigue (9%), palmar-plantar erythrodysesthesia  syndrome (also referred as “hand-foot syndrome”)(7%), vomiting (4%), abdominal pain (3%), hypomagnesemia (3%), and nausea, constipation, rash, increased transaminase, and hypertension (each 1%). At least one dose reduction was reported in 37% of patients. Less frequent important medical events, regardless of causality, were hemorrhage (11% all CTCAE grades, 0% CTCAE grade 3 or 4), venous thrombosis (6% all CTCAE grades, 4% CTCAE grade 3 or 4), and gastrointestinal perforation (6% all CTCAE grades, 0% CTCAE grade 3 or 4).

To access the cabozantinib clinical study data information, please visit www.exelixis.com/sites/default/files/pdf/ASCO_2011-XL184-Ovarian.pdf

Six Deaths Reported (Including Two Ovarian Cancer Patients)

If you examine the Exelixis press release dated June 4 (entitled, Exelixis’ Cabozantinib Demonstrates Encouraging Clinical Activity in Patients with Metastatic Ovarian Cancer — Disease control rate of 53% at week 12, response rate of 24%), which addresses data for cabozantinib use in advanced ovarian cancer patients, pay particular attention to the wording under the heading entitled, “Safety and Tolerability.”  Within the wording set forth under that heading, you will find the following statement: “Two cabozantinib-related grade 5 AEs [adverse events], one enterocutaneous fistula and one intestinal perforation, were reported after the Lead-In phase.” Pursuant to the CTCAE guidelines, a “grade 5 adverse event” is defined as “death related to AE [adverse event].”

We should also note that the two ovarian cancer deaths were summarized briefly in the ASCO presentation regarding cabozantinib use in advanced ovarian cancer.

The reporting of all six deaths is set forth in the Exelixis press release, dated June 5, 2011 (entitled, Exelixis’ Cabozantinib Demonstrates Broad Clinical Activity in Multiple Tumor Types), in similar fashion. Within this release, the sentence provided under the heading “Safety and Tolerability” states: “There were 6 (1%) cabozantinib-related grade 5 [adverse] events, all of which were reported after the Lead-In phase of the trial: respiratory compromise (breast cancer), hemorrhage (NSCLC [non-small cell lung cancer]), enterocutaneous perforation (ovarian cancer), intestinal perforation (ovarian cancer), gastrointestinal hemorrhage (pancreatic cancer), and death (CRPC [castrate resistant prostate cancer]).”

Exelixis Chief Executive Michael Morrissey said the safety statistics are consistent with targeted cancer therapies like cabozantinib that block a pathway used by tumor cells to secure blood vessels.

Cowen & Co analyst Eric Schmidt said the rate of cabozantinib treatment-related deaths — 1 percent — was “no different from what we have seen for every other Phase 1 and 2 trials here at ASCO.”

“While drug safety is of less concern in cancer indications than in others, the apparent morbidities associated with cabo[zantinib] use will confound interpretation of clinical benefit in a trial designed to show anything less than overall survival,” Canaccord analyst George Farmer said in a research note.

In a note to investors, Piper Jaffray analyst Edward Tenthoff said: “The company is exploring lower doses, but the concern is that cabo[zantinib] will not retain the impressive efficacy seen to date.”

Mr. Morrissey said Exelixis plans to move forward with the current daily 100 mg dose of the drug.

Dr. Nicholas J. Vogelzang (Director, Comprehensive Cancer Centers of Nevada) Discusses Mortalities in the Cabozantinib (XL184) Trial

Take Away Message

  • Cabozantinib demonstrates promising activity in both platinum drug-sensitive and platinum drug-resistant/-refractory ovarian cancer.
  • Week 12 overall disease control rate of 53%.
  • Response rates of 18% in platinum-refractory, 22% in platinum-resistant and 28% in platinum-sensitive patients.
  • Cabozantinib shows encouraging duration of response.
  • After 36 weeks of follow-up, median duration of response not reached.
  • Tolerability profile is consistent with that of other tyrosine kinase inhibitors (6 solid tumor patient deaths (1% of all solid tumor pts), including 2 ovarian cancer patients (3% of ovarian cancer pts)).
  • Discordant effects observed between CA-125 changes and clinical activity.
  • Simultaneous targeting of MET and VEGFR2 with cabozantinib results in robust effects in patients with advanced ovarian cancer.
  • Non-randomized expansion cohort is currently accruing in platinum-resistant/-refractory ovarian cancer.

About the MET & VEGFR2 Pathways

To learn more about (i) the role of MET in cancer, (ii) the relationship between the MET and VEGFR pathways, and (iii) the dual inhibition of MET and VEGFR2, visit http://www.metinhibition.com/.

About Cabozantinib (XL184)

Cabozantinib (XL184) is a potent, dual inhibitor of MET and VEGFR2. Cabozantinib is an investigational agent that provides coordinated inhibition of metastasis and angiogenesis to kill tumor cells while blocking their escape pathways. The therapeutic role of cabozantinib is currently being investigated across several tumor types. MET is upregulated in many tumor types, thus facilitating tumor cell escape by promoting the formation of more aggressive phenotypes, resulting in metastasis. MET-driven metastasis may be further stimulated by hypoxic conditions (i.e., deprivation of adequate oxygen supply) in the tumor environment, which are often exacerbated by selective VEGF-pathway inhibitors. In preclinical studies, cabozantinib has shown powerful tumoricidal, anti-metastatic and anti-angiogenic effects, including: (i) extensive apoptosis of malignant cells; (ii) decreased tumor invasiveness and metastasis; (iii) decreased tumor and endothelial cell proliferation; (iv) blockade of metastatic bone lesion progression; and (v) disruption of tumor vasculature.

About Exelixis

Exelixis, Inc. is a biotechnology company committed to developing small molecule therapeutics for the treatment of cancer. Exelixis is focusing its resources and development efforts exclusively on cabozantinib, its most advanced solely-owned product candidate, in order to maximize the therapeutic and commercial potential of this compound. Exelixis believes cabozantinib has the potential to be a high-quality, differentiated pharmaceutical product that can make a meaningful difference in the lives of patients. Exelixis has also established a portfolio of other novel compounds that it believes have the potential to address serious unmet medical needs. For more information, please visit the company’s web site at www.exelixis.com

Sources: 

Cabozantinib (XL184) Clinical Trial Information
Related Libby’s H*O*P*E*™ Postings
Related Libby’s H*O*P*E*™ Videos

ASCO 2011: Novel Multi-targeted Agent Cabozantinib (XL184) Has Significant Effect on Several Advanced Solid Tumors

Cabozantinib (XL184) demonstrated high rates of disease control in patients with prostate, ovarian and liver cancers. The investigators concluded that cabozantinib exhibits clinical activity in ovarian cancer patients with advanced disease, regardless of prior platinum drug status, as reflected by the high rates of response. 

ASCO Releases Studies From Upcoming Annual Meeting – Important Advances in Targeted Therapies, Screening, and Personalized Medicine

The American Society of Clinical Oncology (ASCO) today highlighted several studies in a press briefing from among more than 4,000 abstracts publicly posted online at http://www.asco.org in advance of ASCO’s 47th Annual Meeting. An additional 17 plenary, late-breaking and other major studies will be released in on-site press conferences at the Annual Meeting.

The meeting, which is expected to draw approximately 30,000 cancer specialists, will be held June 3-7, 2011, at McCormick Place in Chicago, Illinois. The theme of this year’s meeting is “Patients. Pathways. Progress.”

“This year marks the 40th anniversary of the signing of the National Cancer Act, a law that led to major new investments in cancer research. Every day in our offices, and every year at the ASCO meeting, we see the results of those investments. People with cancer are living longer, with a better quality of life, than ever before,” said George W. Sledge Jr., M.D., President of ASCO, Ballve-Lantero Professor of Oncology and professor of pathology and laboratory medicine at the Indiana University School of Medicine.

“With our growing understanding of the nature of cancer development and behavior, cancer is becoming a chronic disease that a growing number of patients can live with for many years,” said Dr. Sledge. “The studies released today are the latest examples of progress against the disease, from new personalized treatments, to new approaches to screening and prevention.”

The study results from a phase II clinical trial involving cabozantinib (XL184) were highlighted today in the ASCO press briefing, as summarized below.

Novel Multi-targeted Agent Cabozantinib (XL184) Has Significant Effect on Several Advanced Solid Tumors, and Can Shrink or Eliminate Bone Metastases 

Cabozantinib (XL184) – an oral inhibitor of MET and VEGFR2 kinases involved in the development and progression of many cancers – showed strong responses in patients with various advanced cancers in a phase II trial. The drug demonstrated particularly high rates of disease control for advanced prostate, ovarian and liver cancers, which are historically resistant to available therapies. The drug also fully or partially eliminated bone metastases in patients with breast and prostate cancers and melanoma.

Michael S. Gordon, M.D., President & Chief Executive Officer, Pinnacle Oncology Hematology.

“Cabozantinib appears to have significant effects on several treatment-resistant tumors, as well as impressive effects on bone metastases. In addition, these effects are associated with rapid improvement in pain, a reduction in opiate narcotic requirements and improvement in anemia,” said lead author Michael S. Gordon, M.D., a medical oncologist at Pinnacle Oncology Hematology located in Scottsdale, Arizona. “The implications of these results are very exciting—it is unusual to find a targeted therapy, absent of a molecular mutation in tumors, that works in bony disease and has this activity.”

To be eligible for the study, patients had to have advanced, progressive solid tumors, with or without bone metastases. Of 398 evaluable patients (of 483 enrolled in the trial), 39 percent had bone metastases at baseline. Patients received cabozantinib over 12 weeks. The trial was designed as a “discontinuation” trial, in which those who had partial responses stayed on the drug; those with stable disease were randomized to cabozantinib or placebo; and patients with progressive disease were removed from the trial. This novel type of clinical trial design more quickly evaluates the disease-stabilizing activity of growth-inhibitory agents like cabozantinib, compared to the traditional model of randomizing all patients to either the experimental arm or placebo.

Among 398 patients evaluable with all types of cancer included in the trial, the collective overall response rate was 9 percent (34 of 398). The highest disease control rates (partial response and stable disease) at week 12 were 76 percent for liver cancer (22 of 29 patients), 71 percent for prostate cancer (71 of 100 patients), and 58 percent for ovarian cancer (32 of 51 patients). [emphasis added].

Of the 51 evaluable ovarian cancer patients noted above, 28 are platinum drug resistant, 17 are platinum drug sensitive, and 6 have unknown status. The median number of systemic treatments prior to trial enrollment was 2. The overall response rate (complete response and partial response based on modified RECIST criteria) for ovarian cancer was 12/51 (24%).  Upon breakdown, the response rate was 5/28 (18%) for platinum drug resistant patients, and 5/17 (29%) for platinum drug sensitive patients. Five additional partial responses await confirmation. After a median follow-up of 4 months (range: 1 to 11 months), the median duration of response and median progression free survival have not been reached. The most common related adverse events ( ≥grade 3) among ovarian cancer patients were hand-foot syndrome (10%), diarrhea (8%) and fatigue (4%). Drug dose reductions and permanent discontinuations for adverse events occurred in 43% and 10% of the ovarian cancer patients, respectively. Based on these findings, the investigators concluded that cabozantinib exhibits clinical activity in ovarian cancer patients with advanced disease, regardless of prior platinum drug status, as reflected by the high rates of response. [emphasis added] Accordingly, randomization in the ovarian cancer cohort was halted & patients unblinded due to the observed high efficacy.

Fifty-nine of 68 patients with bone metastases (including patients with breast and prostate cancers and melanoma) experienced either partial or complete disappearance of the cancer on bone scans, often with significant pain relief and other improved cancer-related symptoms.

The reduction of bone metastases and pain relief was an unexpected finding in this study, Dr. Gordon said. Independent review by radiologists confirmed that bone metastases disappeared in the majority of patients who had bone metastases when they entered the study. The majority of these patients had castration-resistant prostate cancer (CRPC), but patients with breast cancer and melanoma also had disappearance of bone metastases. Bone metastases greatly contribute to morbidity and mortality in patients with these types of cancer, which typically spread to the bone.

Due to these results, the study has been expanded to include more CRPC patients. Similarly, the high rate of lasting responses in ovarian cancer patients led researchers to also expand the study to evaluate the drug’s effect on patients with a particularly resistant form of the disease known as platinum drug resistant/refractory ovarian cancer. [emphasis added]

This study expansion results will help determine the design of future phase III trials, which will assess whether the drug extends patients lives or has other longer-term benefits among patients with specific cancer types. At present, cabozantinib is being investigated for use as a single agent. Additional studies will evaluate the efficacy and tolerability of appropriate combinations with other agents for future indications.

For the solid tumor patients collectively, the most common grade three or above adverse events were fatigue (9 percent) and hand-foot syndrome (8 percent). Dose reductions were required in 41 percent of patients due to side effects; 12 percent were removed from the trial for adverse events.

Sources:

Resources:

Cabozantinib (XL184) Clinical Trials:

Related Libby’s H*O*P*E*™ Postings:

ASCO 2011: Maintenance Therapy With PARP Inhibitors Could Play Important Role in Treatment of Recurrent Ovarian Cancer

A randomized phase II clinical trial showed that the oral PARP inhibitor drug olaparib (AZD2281), given after chemotherapy, improved progression-free survival in women with the most common type of recurrent ovarian cancer.

ASCO Releases Studies From Upcoming Annual Meeting – Important Advances in Targeted Therapies, Screening, and Personalized Medicine

The American Society of Clinical Oncology (ASCO) today highlighted several studies in a press briefing from among more than 4,000 abstracts publicly posted online at http://www.asco.org in advance of ASCO’s 47th Annual Meeting. An additional 17 plenary, late-breaking and other major studies will be released in on-site press conferences at the Annual Meeting.

The meeting, which is expected to draw approximately 30,000 cancer specialists, will be held June 3-7, 2011, at McCormick Place in Chicago, Illinois. The theme of this year’s meeting is “Patients. Pathways. Progress.”

“This year marks the 40th anniversary of the signing of the National Cancer Act, a law that led to major new investments in cancer research. Every day in our offices, and every year at the ASCO meeting, we see the results of those investments. People with cancer are living longer, with a better quality of life, than ever before,” said George W. Sledge Jr., M.D., President of ASCO, Ballve-Lantero Professor of Oncology and professor of pathology and laboratory medicine at the Indiana University School of Medicine.

“With our growing understanding of the nature of cancer development and behavior, cancer is becoming a chronic disease that a growing number of patients can live with for many years,” said Dr. Sledge. “The studies released today are the latest examples of progress against the disease, from new personalized treatments, to new approaches to screening and prevention.”

The study results from a phase II clinical trial involving maintenance therapy with the PARP (poly (ADP-ribose) polymerase) inhibitor olaparib were highlighted today in the ASCO press briefing, as summarized below.

Randomized Study Shows that Maintenance Therapy With PARP Inhibitors Could Play Important Role in Treatment of Recurrent Ovarian Cancer

A phase II randomized trial showed that maintenance treatment with the oral PARP inhibitor drug olaparib (AZD2281) improved progression-free survival by about four months in women with the most common type of relapsed ovarian cancer. This is the first randomized trial to demonstrate a benefit for maintenance therapy for recurrent ovarian cancer, and the first randomized trial in ovarian cancer of a PARP inhibitor– a novel class of molecularly targeted drugs.

The results of this study, if confirmed in larger trials, could lead to a new treatment approach for recurrent ovarian cancer in which drugs like olaparib are given over a long period of time to prevent recurrences or prolong remissions. This somewhat novel approach, called maintenance therapy, has already proven useful in lung cancer. Standard treatment for ovarian cancer includes platinum-based chemotherapy. After this regimen, patients are observed until recurrence, and then treated with another course of chemotherapy. While some tumors respond well to chemotherapy, the regimens are too toxic for patients to take continuously, and clinical trials have not shown any benefit for extended courses of chemotherapy.

Jonathan A. Ledermann, M.D., Lead Author & Principal Investigator of PARP Maintenance Study; Professor, Medical Oncology, UCL Cancer Institute, University College London

“A well-tolerated antitumor agent that could be used for months or perhaps years as maintenance therapy after standard chemotherapy could be a big step forward and ultimately extend survival,” said lead author Jonathan A. Ledermann, M.D., principal investigator of the study and Professor of Medical Oncology at UCL Cancer Institute, University College London. “This study demonstrates proof of principle for the concept of maintenance therapy in ovarian cancer using a PARP inhibitor. Our progression-free survival difference was very impressive and better than we anticipated.”

The multicenter, international study randomized 265 women with high-grade serous ovarian cancer to either olaparib or placebo. Patients were enrolled in the trial within 8 weeks of having achieved either a complete or partial response to platinum-based treatment. PARP inhibitors have been shown to work better in patients whose tumors have responded to platinum.

In the study, the progression-free survival (PFS) – the amount of time during and after treatment in which the cancer does not return – was significantly longer in the group receiving olaparib than the placebo group, with a median of 8.4 months versus 4.8 months. At the time of data analysis, half the patients randomized to olaparib (68 patients) had not relapsed and were still receiving the drug, while only 16 percent (21 patients) remained on placebo – so overall survival data were not yet available for analysis.

Adverse events were more commonly reported in the group receiving olaparib than placebo, including nausea, fatigue, vomiting, and anemia, but the majority of these were not severe. Dose reductions to manage side effects were allowed in the study and were more prevalent in the olaparib group (23 percent) compared to the placebo group (7 percent).

Olaparib inhibits the enzyme poly (ADP-ribose) polymerase — abbreviated “PARP” — which is involved in DNA (deoxyribonucleic acid) repair. Up to half of women with high-grade serous ovarian cancer – the most common type of ovarian cancer – may have a DNA repair deficiency that makes them more susceptible to treatment with PARP inhibitors.

A number of PARP inhibitors are being studied in phase II and phase III clinical trials, as single agents and in combination with standard chemotherapies and radiation, in some types of breast and ovarian cancers believed to have DNA repair defects.

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PARP Clinical Trials:
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Related WORD of HOPE™ Ovarian Cancer Podcasts:
Related Libby’s H*O*P*E*™ Postings:
Related Libby’s H*O*P*E*™ Videos Re PARP Inhibitors


2011 Pharmaceutical Research & Manufacturers of America Report Lists 58 Drugs in Development For Ovarian Cancer

Currently, 851 medicines are in development for diseases that exclusively or disproportionately affect women, according to a report unveiled today by the Pharmaceutical Research and Manufacturers of America (PhRMA).

Currently, 851 medicines are in development for diseases that exclusively or disproportionately affect women, according to a report unveiled today by the Pharmaceutical Research and Manufacturers of America (PhRMA).  The medicines in the pipeline for women (either in human clinical trials or awaiting review by the Food and Drug Administration) include:

• 139 for cancers affecting women, including 91 for breast cancer, 49 for ovarian cancer,[1] and 9 for cervical cancer.

• 114 for arthritis/musculoskeletal disorders. Approximately 46 million Americans have some type of arthritis or related condition, and 60 percent of them are female.

• 64 for obstetric/gynecologic conditions.

• 110 for autoimmune diseases, which strike women three times more than men.

• 72 for depression and anxiety. Almost twice as many women as men suffer from these disorders.

• 83 for Alzheimer’s disease. Two-thirds (3.4 million) of the 5.4 million Americans living with Alzheimer’s today are women.

The Drug Discovery Process

Ovarian cancer affected an estimated 21,880 U.S. women in 2010 and caused an estimated 13,850 deaths.  The PhRMA report highlighted a potential first-in-class ovarian cancer drug (volasertib/BI 6727) in development which works by selectively inhibiting the polo-like kinase-1 (PLK-1), an enzyme crucial for cell division. PLK-1 is expressed in proliferating cells and most tumors. Inhibiting its activity disrupts cell division, which induces cell death and reduces cancer growth.

The ovarian cancer drugs listed in the PhRMA report are listed below by name (brand name, if available, and generic name), manufacturer, and phase of clinical testing. The ovarian cancer drugs listed in the “Cancer” section of the PhRMA report are set forth below:[2]

A6, Angstrom Pharmaceuticals, Phase II.

Abagovomab (anti-idiotype ovarian cancer vaccine)(Orphan Drug), Menarini, Phase I/II.

Abraxane®/albumin-bound paclitaxel, Celgene, Phase II.

ABT-888/veliparib, Abbott Laboratories, Phase II.

AE-37, Antigen Express, Phase I.

Afinitor®/everolimus, Novartis Pharmaceuticals, Phase I/II.

AMG 386, Amgen, Phase III.

AMG 479, Amgen, Phase II.

Avastin®, bevacizumab, Genentech, Phase III.

BC-819, BioCancell Therapeutics, Phase I/II.

Catumaxomab, Fresenius Biotech, Phase II.

CVac™/MUC-2 cancer vaccine, Prima BioMed, Phase II.

DCVax®-L/ovarian cancer vaccine, Northwest Biotherapeutics, Phase I.

DPX-0907, Immunovaccine, Phase I.

EC-145, Endocyte, Phase II.

EGEN-001 (Orphan Drug), EGEN, Phase I/II.

ENMD-2076, EntreMed, Phase II.

Estybon™/ON-01910.Na, Onconova Therapeutics, Phase II.

Evizon™/squalamine, OHR Pharmaceuticals, Phase II.

farletuzumab/MORAb-003, Eisai, Phase III.

iboctadekin, GlaxoSmithKline, Phase I.

IMT-1012/immunotherapeutic vaccine, Immunotope, Phase I.

iniparib/BSI-201, BiPar Sciences/sanofi-aventis, Phase II.

Karenitecin®/cositecan, BioNumerik Pharmaceuticals, Phase III.

KHK-2866, Kyowa Hakko Kirin Pharma, Phase I.

lenvatinib/E7080, Eisai, Phase II.

MK-2206, Merck, Phase I.

Nexavar®/sorafenib, Bayer HealthCare Pharmaceuticals/Onyx Pharmaceuticals, Phase II.

NKTR-102, Nektar Therapeutics, Phase II.

NOV-002, Novelos Therapeutics, Phase II.

OGX-427, Oncogenex Pharmaceuticals, Phase I.

olaparib/AZD2281, AstraZeneca, Phase II.

Opaxio™/paclitaxel poliglumex, Cell Therapeutics/Novartis Pharmaceuticals, Phase III.

Optisome™/topetecan liposomal, Talon Therapeutics, Phase I.

Oregovomab, Quest Pharmatech, Phase I/II.

OSI-906/linsitinib, OSI Pharmaceuticals, Phase II.

OVax®/ovarian cancer vaccine (Orphan Drug), AVAX Technologies, Phase I/II.

Perifosine/KRX-0401, AEterna Zentaris/Keryx Biopharmaceuticals, Phase I.

PF-01367338, Pfizer, Phase II.

Phenoxodiol (next generation drug will be NV-143), Marshall Edwards, Phase III.

Picoplatin intravenous, Poniard Pharmaceuticals, Phase II.

Quinamed®/amonafide, ChemGenex Pharmaceuticals, Phase II.

Ramucirumab/IMC-1121-B, Eli Lilly/ImClone, Phase I.

Ridaforolimus, Merck/Ariad Pharmaceuticals, Phase I.

Sagopilone, Bayer HealthCare Pharmaceuticals, Phase II.

SAR256212/MM-121, Merrimack Pharmaceuticals/sanofi-aventis, Phase I.

SG2000, Spirogen, Phase II.

Sprycel®/dasatinib, Bristol-Myers Squibb, Phase

Tarceva®/erlotinib, Genentech, Phase II.

Telcyta®/canfosfimide, Telik, Phase III.

Tigatuzumab, Daiichi Sankyo, Phase II.

Tykerb®/lapatinib, GlaxoSmithKline, Phase I/II.

Volasertib, Boehringer Ingelheim Pharmaceuticals, Phase II.

Volociximab, Bigen Idec/Facet Biotech, Phase II.

Vosaroxin™/SNS-595, Sunesis Pharmaceuticals, Phase II.

Votrient®/pazopanib, GlaxoSmithKline, Phase III.

Zolinza®/vorinostat, Merck, Phase II.

Zybrestat™/fosbretabulin, OXiGENE, Phase II.

References:

1/The 2011 PhRMA report lists 49 ovarian cancer drugs in development.  After comparing the entire “Cancer” drug list set forth on pages 16 – 24 of the PhRMA report to the ovarian cancer clinical trials provided at http://www.clinicaltrials.gov, we determined that an additional nine drugs appearing on the PhRMA cancer drug list are being tested in ovarian cancer clinical trials.

2/Please note that the PhRMA cancer drug list does not set forth all ovarian cancer drugs in development.  For a list of all open ovarian cancer clinical trials listed at www.clinicaltrials.gov, click here.

Sources:

Resources:

Experimental Drug NVP-BEZ235 Slows Ovarian Cancer Growth in Mice; Solid Tumor Clinical Trials Ongoing

A study conducted recently at UCLA’s Jonsson Comprehensive Cancer Center found that experimental drug NVP-BEZ235, which blocks two points of a crucial cancer cell signaling pathway, inhibits the growth of ovarian cancer cells and significantly increases survival in an ovarian cancer mouse model.

A study conducted recently at  UCLA’s Jonsson Comprehensive Cancer Center (JCCC) found that an experimental drug, which blocks two points of a crucial cancer cell signaling pathway, inhibits the growth of ovarian cancer cells and significantly increases survival in an ovarian cancer mouse model.

Oliver Dorigo, M.D., Ph.D., Assistant Professor, Department of Gynecologic Oncology, Division Gynecologic Oncology, UCLA Jonnson Comprehensive Cancer Center; Member, JCCC Cancer Molecular Imaging Program Area

The Novartis Oncology drug, called NVP-BEZ235, also inhibits growth of ovarian cancer cells that have become resistant to the conventional treatment with platinum chemotherapy and helps to resensitize the cancer cells to the therapy. In addition, it enhances the effect of platinum chemotherapy on ovarian cancer cells that are still responding to the therapy, said the study’s senior author, Dr. Oliver Dorigo, an assistant professor of obstetrics and gynecology and a JCCC researcher.

“Platinum-based chemotherapy drugs are effective in treating ovarian cancers as long as the cancer cells remain sensitive to platinum,” Dorigo said. “But once the tumor becomes resistant, treating the cancer becomes very challenging. This is a significant clinical problem, since the majority of ovarian cancer patients develop resistance at some point during treatment. Breaking chemotherapy resistance is a difficult challenge, but crucial if we want to improve long-term survival for our patients.”

The study, performed on cells lines and mouse models, appears in the April 15 issue of the journal Clinical Cancer Research.

Over the last several years, Dorigo has been working in his laboratory to develop new therapies for ovarian cancer. About 22,000 American women are diagnosed each year with ovarian cancer, and more than 14,000 deaths are attributed to the disease annually. Dorigo has focused his research efforts on a pathway called PI3Kinase/Akt/mTOR, which, once activated, promotes ovarian cancer growth. The activated pathway also makes the cancer more aggressive and more likely to spread to other organs, Dorigo said, so targeting it offers great promise for more effective therapies for the disease.

In this two-year study, Dorigo and postdoctoral fellow Chintda Santiskulvong found that inhibiting two checkpoints of the pathway — PI3Kinase and mTOR — with NVP-BEZ235 decreased cancer growth, both in cell culture dishes and in mice with ovarian cancer. It also significantly increased survival in the mice, he said. More importantly, NVP-BEZ235 slowed growth of the ovarian cancer cells that had become resistant to platinum and helped to break that resistance.

“We were very encouraged to find that NPV-BEZ235 could resensitize the ovarian cancer cells to standard platinum treatment,” Dorigo said. “In addition, we found this drug to be more effective in inhibiting ovarian cancer cell growth than other drugs that target only one checkpoint, mTOR, in this pathway. We believe that NVP-BEZ235 has superior efficacy because of the dual effect on PI3Kinase and mTOR.”

The experimental drug is being tested as a single agent at the Jonsson Cancer Center in human clinical trials against other solid tumors. Researchers involved with those studies have said early results are encouraging.

John Glaspy, M.D., M.P.H., Co-Chief, Department of Medicine, Hematology/Oncology, UCLA Jonnson Comprehensive Cancer Center; JCCC Director, JCCC Clinical Research Unit; Member, Stand Up To Cancer Mangement Committee

“This is clearly a promising agent with activity in humans,” said Dr. John Glaspy, a professor of hematology–oncology and a Jonsson Cancer Center scientist involved with the studies. “We are still assessing its tolerability in patients.”

Dorigo said he hopes to initiate a clinical trial for women with ovarian cancer that tests the combination of NVP-BEZ235 with platinum chemotherapy, as he believes that the combination might be more effective than each drug alone.

The study was funded by the Ovarian Cancer Research Foundation/Liz Tilberis Scholarship, the Gynecologic Cancer Foundation/Florence and Marshall Schwid Ovarian Cancer Award, a STOP Cancer Career Development Award and the National Institutes of Health’s Women’s Reproductive Health Research Program.

About the UCLA Jonnson Comprehensive Cancer Center

UCLA’s Jonsson Comprehensive Cancer Center has more than 240 researchers and clinicians engaged in disease research, prevention, detection, control, treatment and education. One of the nation’s largest comprehensive cancer centers, the Jonsson Center is dedicated to promoting research and translating basic science into leading-edge clinical studies. In July 2010, the center was named among the top 10 cancer centers nationwide by U.S. News & World Report, a ranking it has held for 10 of the last 11 years.

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