Exelixis Reports Promising Interim Data From Ovarian Cancer Patients Treated With XL184

Exelixis reports promising interim data from ovarian cancer patients treated with XL184, including:  a  32% confirmed response rate per RECIST in patients with platinum-resistant or platinum-sensitive disease, and a 64% overall week-12 disease control rate.

Ignace Vergote, M.D., Ph.D., Head, Department of Obstetrics & Gynecology and Gynecologic Oncology, Catholic University Hospital, Leuven, Belgium

Exelixis, Inc.  today reported interim data from the cohort of patients with advanced epithelial ovarian cancer, primary peritoneal, or fallopian tube carcinoma treated with XL184 in an ongoing phase 2 adaptive randomized discontinuation trial (RDT) [1]. Ignace Vergote, M.D., Ph.D., Head of the Department of Obstetrics and Gynecology and Gynecologic Oncology at the Catholic University Hospital Leuven, Leuven, Belgium, will present the data in the Molecular-Targeted Therapies-Clinical Trials poster session (Abstract #407) on Thursday, November 18th, at the 22nd EORTC-NCI-AACR [2] Symposium on Molecular Targets and Cancer Therapeutics, being held in Berlin, Germany.

XL184 Activity in Patients with Ovarian Cancer

XL184 is an oral, potent inhibitor of MET, VEGFR2 and RET. MET overexpression has been observed in advanced ovarian cancer, and anti-VEGF pathway agents have shown clinical benefit in ovarian cancer patients. For these reasons, co-targeting of the MET and VEGF signaling pathways using XL184 may represent a promising treatment strategy.

As of the November 1, 2010 cut-off date, a total of 51 patients were enrolled into the ovarian cancer cohort, with 31 evaluable for response, and 41 evaluable for safety. The median number of prior systemic treatments was 2. Tumor shrinkage was observed in 30 of 37 (81%) patients with measurable metastatic lesions. Of 31 patients evaluable for response per RECIST (Response Evaluation Criteria In Solid Tumors), 10 (32%) achieved a confirmed partial response (PR). Stable disease (SD) was reported in 15 patients (48%) including 3 patients who achieved unconfirmed PRs. The overall week-12 disease control rate (DCR)(complete responses + partial responses + stable disease responses = DCR) was 64%.

Upon subset analysis, 5 of 17 platinumrefractory or –resistant patients (29%) evaluable for response per RECIST achieved a confirmed PR. SD was reported in 7 patients (41%) including 2 patients with unconfirmed PRs. The week-12 DCR was 59% in platinum-resistant/refractory patients. Durable responses have been observed, including 2 patients with platinum-refractory or resistant disease who remain on study for 34+ and 36+ weeks, and 3 patients with platinum-sensitive disease on study for 24, 24+, and 28+ weeks. Some patients have experienced reductions in the ovarian cancer blood marker CA125, but in general no clear concordance between CA125 changes and tumor shrinkage has been observed.

Safety data are available for 49 patients who had at least 6 weeks of follow-up. The most common grade greater-than or equal to 3 adverse events, regardless of causality were PPE (Palmar-Plantar Erythrodysesthesia) syndrome (also referred to as “hand-foot syndrome”) (12%), diarrhea (7%), fatigue, vomiting (each 5%), nausea, rash, abdominal pain, hypertension, and hypomagnesemia (each 2%).

“The activity of XL184 in women with both platinum-sensitive and platinum-resistant/refractory disease is unique and encouraging. The response rate and overall disease control rate of this oral agent are impressive especially in the group of patients with platinum refractory/resistant ovarian cancer, and compare favorably to other targeted and systemic agents in development,” said, Dr. Vergote. “I believe these encouraging data warrant further evaluation of XL184 in ovarian cancer.”

Michael M. Morrissey, Ph.D., President & Chief Executive Officer, Exelixis, Inc.

“The high response rate in patients with ovarian cancer is reflective of the broad anti-tumor activity of XL184 observed in multiple tumor types to date,” said Michael M. Morrissey, Ph.D., president and chief executive officer of Exelixis. “The data from the RDT underscore the novel and differentiated clinical activity of XL184 in diverse tumor indications with predominance of either soft tissue or bone involvement.”

To access the clinical data poster mentioned in this press release, please visit www.exelixis.com.

Broad Clinical Activity of XL184 – Randomized Discontinuation Trial

XL184 has demonstrated anti-tumor activity in 9 of 12 indications studied to date. In ongoing trials, compelling activity has been observed in medullary thyroid cancer, glioblastoma, and clear cell renal cancer. In the RDT, XL184 is being evaluated in nine different tumor types, with clear signals of activity in six: prostate, ovarian, hepatocellular, breast, non-small cell lung cancer and melanoma. The adaptive RDT design allowed for rapid simultaneous assessment of the activity of XL184 across nine different tumor indications. As of the November 1, 2010 cut-off date, a total of 397 patients have been enrolled into the nine disease-specific cohorts, with 273 evaluable for response, and 312 evaluable for safety. Of 273 patients evaluable for response per RECIST, 39 achieved a PR (either confirmed or unconfirmed) and 100 had SD at week 12. The week-12 DCR for the overall population was 49%, with the highest rates occurring in hepatocellular cancer (75%), castration-resistant prostate cancer (71%), ovarian cancer (64%), melanoma (45%), non-small cell lung cancer (42%) and breast cancer (42%). Of note, a breast cancer patient with evidence of bone metastasis on bone scan demonstrated evidence of resolution on bone scan accompanied by 29% reduction in tumor size. XL184 has been generally well tolerated with a consistent adverse event profile across the nine different RDT tumor types.

About XL184

XL184, an inhibitor of tumor growth, metastasis and angiogenesis, simultaneously targets MET and VEGFR2, key kinases involved in the development and progression of many cancers, including ovarian cancer. It has recently been shown in preclinical models that treatment with selective inhibitors of VEGF signaling can result in tumors that are more invasive and aggressive compared to control treatment. In preclinical studies, upregulation of MET has been shown to occur in concert with development of invasiveness after selective anti-VEGF therapy, and may constitute a mechanism of acquired or evasive resistance to agents that target VEGF signaling. Accordingly, treatment with XL184 in similar preclinical studies resulted in tumors that were less invasive and aggressive compared to control or selective anti-VEGF treatment. Therefore, XL184 has the potential for improving outcomes in a range of indications, including those where selective anti-VEGF therapy has shown minimal or no activity.

About Exelixis

Exelixis, Inc. is a development-stage biotechnology company dedicated to the discovery and development of novel small molecule therapeutics for the treatment of cancer. The company is leveraging its biological expertise and integrated research and development capabilities to generate a pipeline of development compounds with significant therapeutic and commercial potential for the treatment of cancer. Currently, Exelixis’ broad product pipeline includes investigational compounds in phase 3, phase 2, and phase 1 clinical development. Exelixis has established strategic corporate alliances with major pharmaceutical and biotechnology companies, including Bristol-Myers Squibb Company, sanofi-aventis, GlaxoSmithKline, Genentech (a wholly owned member of the Roche Group), Boehringer Ingelheim, and Daiichi-Sankyo. For more information, please visit the company’s web site at http://www.exelixis.com.

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1/Rosner GL, Stadler W, Ratain MJ. et. al.  Randomized discontinuation design: Application to cytostatic antineoplastic agents. J Clin Oncol 20:4478-4484, 2002.  Pursuant to this design, all patients receive the investigational drug for an initial period of time. Patients with standard radiologic tumor shrinkage within that timeframe would continue investigational therapy, while those with radiologic progression or unacceptable toxicity would discontinue therapy. All patients with radiologic stable disease after the initial therapy period are then randomized to continuing or discontinuing therapy in a double-blind placebo-controlled manner. This is an enrichment strategy in which patients with the end point of interest are preferentially enrolled in the randomized portion and in which the heterogeneity of the randomized population is decreased. These two factors result in an increased power for detecting a clinically relevant difference and decrease the number of patients exposed to placebo. Importantly, the enrichment is driven by the properties of the investigational drug as opposed to clinical prognostic factors identified in historical untreated patients or patients treated with a different class of agents. In addition, the statistical behavior of the trial is not highly dependent on investigators’ assumptions regarding the “no dose effect” (i.e., non-receipt of drug = no effect)  for time to progression or stable disease rate, and thus effectively deals with uncertainty in this variable. Finally, patients may find such a trial design more appealing, resulting in brisk accrual.

2/EORTC [European Organisation for Research and Treatment of Cancer, NCI [National Cancer Institute], AACR [American Association for Cancer Research].

PARP Inhibitor Olaparib Benefits Women With Inherited Ovarian Cancer Based Upon Platinum Drug Sensitivity

Olaparib (AZD2281), a new type of cancer drug known as a “PARP inhibitor,” produced promising results in patients with platinum-refractory, platinum-resistant, and platinum-sensitive ovarian cancer linked to an inherited BRCA1 or BRCA2 gene mutation.

A new type of cancer drug — known as a “PARP inhibitor” — produced promising results in patients with ovarian cancer linked to an inherited BRCA1 or BRCA2 gene mutation. The trial results were published online in the Journal of Clinical Oncology on April 19th.

Scientists at The Institute of Cancer Research (ICR) and The Royal Marsden Hospital, working with pharmaceutical company KuDOS Pharmaceuticals, now a subsidiary of AstraZeneca, found the experimental drug olaparib shrank or stabilized tumors in approximately half of ovarian cancer patients possessing BRCA1 or BRCA2 mutations.

The five-year survival rate for ovarian cancer is just 40 per cent as the majority of patients are diagnosed with an advanced form of the disease. Most patients initially respond well to radical surgery and platinum and taxane-based chemotherapy, but relapse after an average of 18 months. Subsequent treatments generally become less effective as patients build up resistance.

Professor Stan Kaye, Head of Section of Medicine, Institute of Cancer Research; Head of Drug Development Unit, The Royal Marsden Hospital; and Cancer Research UK-funded scientist

“There is an urgent need to find new drugs for women diagnosed with ovarian cancer,” says Professor Stan Kaye, Head of the Section of Medicine at the ICR and Head of the Drug Development Unit at The Royal Marsden Hospital and a Cancer Research UK-funded scientist. “Olaparib is still in early-stage testing but the results so far are very encouraging. These findings raise the possibility that carefully selected patients in future may well be offered olaparib as an alternative to chemotherapy during the course of their treatment.”

Between 2005 and 2008, about 50 women with confirmed or suspected BRCA1 or BRCA2 mutations began treatment with olaparib in a dose escalation and single-stage expansion of a Phase I trial. Twenty patients responded with their tumors shrinking or with significant falls in their ovarian cancer marker CA125, or both. The disease also stabilized in three patients. The drug was effective for an average of seven months. Notably, several patients are still taking olaparib (for nearly two years). Drug side-effects were generally mild, especially when compared to current chemotherapy treatments.

Olaparib is a new type of drug known as a PARP inhibitor that works by turning a tumor’s specific genetic defect against itself. In susceptible cells, olaparib prevents the repair of naturally occurring breaks in DNA, which healthy cells are able to repair. Susceptible cancer cells – those with an existing defect in a DNA repair pathway caused by a mutation in the BRCA1 or BRCA2 genes – are unable to repair themselves, and therefore, die.

Platinum-based chemotherapy, particularly carboplatin, is one of the main treatments used for ovarian cancer. When this treatment ceases to be effective, theoretically, olaparib might be less effective too, so the ICR scientists examined whether olaparib would still benefit patients whose response to previous platinum-based drugs was limited. Finding new drugs to treat these “platinum-resistant” ovarian cancer patients (those who relapsed within six months of previous platinum therapy) is a particularly high priority as they have a lower chance of benefiting from re-treatment with chemotherapy and a poorer prognosis.

The research team found that the clinical benefit rate with olaparib was indeed higher — 70% — among patients with “platinum-sensitive disease” (disease recurrence more than six months after previous platinum therapy). Crucially, however, the clinical benefit rate was still 46% in platinum resistant patients.

ICR Study Findings:

  • 50 patients participated in the study (13 had platinum-sensitive disease, 24 had platinum-resistant disease, and 13 had platinum-refractory disease (according to platinum-free interval).
  • 20 patients (40%) achieved complete or partial responses under RECIST (Response Evaluation Criteria in Solid Tumors) criteria and/or tumor marker (CA125) responses.
  • Overall clinical benefit rate (complete response + partial response + stable disease) = 46%.
  • Median response duration was 28 weeks.
  • There was a significant association between the clinical benefit rate and platinum-free interval across the platinum-sensitive, resistant, and refractory patient subgroups (69%, 45%, and 23%, respectively).
  • Analyses indicated associations between platinum sensitivity and extent of olaparib response.
  • CONCLUSION: Olaparib has antitumor activity in BRCA1/2 mutation ovarian cancer, which is associated with platinum sensitivity.

Up to 15 per cent of breast and ovarian cancers have known BRCA1 or BRCA2 mutations on blood testing and, importantly, laboratory data strongly suggests that olaparib may also be effective in cancers linked to DNA repair defects not caused by BRCA1 and BRCA2 mutations. This could apply in about half the cases of the most common histological type of ovarian cancer.

“We have good reason for thinking that the benefit seen with olaparib in BRCA mutation-linked ovarian cancer may well extend to a broader population of patients with this disease,” says Professor Kaye.

Randomised trials of olaparib – in which some patients receive the drug and others a placebo – are underway and results will be available later this year.

KuDOS Pharmaceuticals (a wholly owned subsidiary of AstraZeneca) was the major funder of the trial, along with Cancer Research UK and the National Institute for Health Research. Olaparib was identified and developed at KuDOS Pharmaceuticals and subsequently at AstraZeneca.

PARP Inhibitor Clinical Trials:

To view a list of open ovarian cancer clinical trials that are testing olaparib (AZD2281), click here.

To view a list of open solid tumor clinical trials that are testing olaparib (AZD2281), click here.

To view a list of open ovarian cancer clinical trials that are testing various PARP inhibitors, click here.

To view a list of open solid tumor clinical trials that are testing various PARP inhibitors, click here.

About The Institute of Cancer Research (ICR)

* The ICR is Europe’s leading cancer research centre.

* The ICR has been ranked the UK’s top academic research centre, based on the results of the Higher Education Funding Council’s Research Assessment Exercise.

* The ICR works closely with partner The Royal Marsden NHS Foundation Trust to ensure patients immediately benefit from new research. Together the two organisations form the largest comprehensive cancer centre in Europe.

* The ICR has charitable status and relies on voluntary income, spending 95 pence in every pound of total income directly on research.

* As a college of the University of London, the ICR also provides postgraduate higher education of international distinction.

* Over its 100-year history, the ICR’s achievements include identifying the potential link between smoking and lung cancer which was subsequently confirmed, discovering that DNA damage is the basic cause of cancer and isolating more cancer-related genes than any other organization in the world.

* The ICR is home to the world’s leading academic drug development team. Several important anti-cancer drugs used worldwide were synthesised at the ICR and it has discovered an average of two preclinical candidates each year over the past five years.

For more information visit www.icr.ac.uk.

About The Royal Marsden Hospital

The Royal Marsden opened its doors in 1851 as the world’s first hospital dedicated to cancer treatment, research and education. Today, together with its academic partner, The Institute of Cancer Research, it is the largest and most comprehensive cancer centre in Europe treating over 40,000 patients every year. It is a centre of excellence, and the only NHS Trust to achieve the highest possible ranking in the Healthcare Commission’s Annual Health Check for the third year in a row. Since 2004, the hospital’s charity, The Royal Marsden Cancer Campaign, has helped raise over £43 million to build theatres, diagnostic centres, and drug development units. Prince William became President of The Royal Marsden in 2007, following a long royal connection with the hospital.

For more information, visit www.royalmarsden.nhs.uk

About Cancer Research UK

* Cancer Research UK is the world’s leading charity dedicated to beating cancer through research.

* The charity’s groundbreaking work into the prevention, diagnosis and treatment of cancer has helped save millions of lives. This work is funded entirely by the public.

* Cancer Research UK has been at the heart of the progress that has already seen survival rates double in the last thirty years.

* Cancer Research UK supports research into all aspects of cancer through the work of more than 4,800 scientists, doctors and nurses.

* Together with its partners and supporters, Cancer Research UK’s vision is to beat cancer.

For further information about Cancer Research UK’s work or to find out how to support the charity, please call 020 7121 6699 or visit www.cancerresearchuk.org

About Experimental Cancer Medicine Centre (ECMC)

Experimental Cancer Medicine Centre (ECMC) status has been awarded to 19 centres in the UK that are specialist centres conducting research into new cancer treatments. The aim is to bring together cancer doctors, research nurses and lab scientists to make clinical trials of new treatments quicker and easier. The ECMC initiative is funded by Cancer Research UK and the Departments of Health of England, Scotland, Wales and Northern Ireland. Together they are giving a total of £35 million pounds over five years to the 19 centres. The centres will use this money to run trials of new and experimental treatments. They will also analyse thousands of blood and tissue samples (biopsies) to help find out more about how treatments work and what happens to cancer cells.

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Endocyte’s EC145 Produces Significant Anti-Tumor Activity In Advanced Stage Chemoresistant Ovarian Cancer Patients

Endocyte, Inc., … presented data from a Phase 2a clinical trial for EC145, … In 49 women with advanced-stage ovarian cancer, EC145 was shown to have anti-tumor activity in a significant percentage of participants in the trial. …[T]he overall disease control rate, defined as stable disease, partial or complete response to therapy, was 40.8 percent (20 of 49). … In the subgroup of patients who were EC20 “positive” and who had failed four or fewer prior therapies, the disease control rate was 75 percent (9 of 12) and two patients exhibited a RECIST partial response. …

EC20 Imaging Results

Companion diagnostic images of ovarian cancer patients using folate-receptor targeted imaging agent (EC20-Tc99m). Patient on the top shows no targeting to tumor (negative profile). Patient on the bottom shows targeting to tumor (positive profile)(Photo: Endocyte, Inc.)

Endocyte, Inc., a cancer drug discovery and development company, presented data from a Phase 2a clinical trial for EC145, currently in development as a potential treatment for advanced ovarian cancer. Results were presented at the European Society of Gynaecologic Oncology (ESGO) meeting in Belgrade, Serbia last week. In 49 women with advanced-stage ovarian cancer, EC145 was shown to have anti-tumor activity in a significant percentage of participants in the trial.

The study participants had disease that was highly resistant to standard chemotherapy. Subjects had a median of four prior exposures to chemotherapy (with a range of 1 to 14), and 88 percent were diagnosed with “bulky disease,” defined as having a tumor volume of greater than five centimeters in diameter. However, in spite of this, the overall disease control rate, defined as stable disease, partial or complete response to therapy, was 40.8 percent (20 of 49).

Prior to the start of treatment with EC145, the women were scanned with 99mTc-EC20 [EC20], a molecular imaging agent that binds to folate receptors (FR) and is being developed by Endocyte as a companion diagnostic tool to identify patients whose tumors express FR, the molecular target for the EC145 therapy. When scanned with EC20, 76 percent of patients were found to be folate-receptor “positive.” In the subgroup of patients who were EC20 “positive” and who had failed four or fewer prior therapies, the disease control rate was 75 percent (9 of 12) and two patients exhibited a RECIST partial response. Across all patients, the drug was well tolerated with no grade 4 toxicities. The most common grade 3 toxicity was fatigue (8.2 percent).

According to Dr. Richard Messmann, Endocyte’s VP for medical affairs, “These preliminary results provide significant additional support for Endocyte’s technology platform and for the important role that Endocyte’s co-development of targeted therapeutics and companion diagnostics can play in cancer drug discovery. Based upon these promising results, EC145 is now being evaluated in our Phase 2b PRECEDENT study, an international randomized study of EC145 in combination with Doxil®/Caelyx® versus Doxil®/Caelyx® alone in women with platinumresistant ovarian cancer.”

About Endocyte

EC145 PRECEDENT Clinical TrialEndocyte is a privately held biotechnology company with headquarters in the Purdue Research Park of West Lafayette, IN. Based on the applications of Endocyte’s advanced proprietary Drug Guidance System (DGS), the company is working to develop new drugs and diagnostic agents to treat many types of cancer and other serious diseases. The DGS platform makes it possible to use highly potent drugs on extended and frequent dosing schedules and in combination with other drugs to maximize efficacy. The technology improves drug targeting and reduces the risk of side effects by combining drugs with ligands that are able to identify and attach to receptors found on tumor and other disease cells. Endocyte’s clinical development of EC20 and EC145 is progressing with the recent completion of accrual for the Phase 2a trials in advanced ovarian and lung cancer. EC20 and EC145 are now being studied in an international Phase 2b trial of EC145 in combination with Doxil® for the treatment of women with platinum resistant ovarian cancer. Other clinical-stage products in the Endocyte pipeline include EC0225, a targeted combination of two potent anticancer drugs; BMS753493, a potent drug being developed in partnership with Bristol-Myers Squibb; EC0489, a targeted cancer drug; and EC17, a targeted immunotherapy agent. The company also has multiple product candidates in pre-clinical stage of development.

Information about the PRECEDENT study can be found at http://clinicaltrials.gov/ct2/show/NCT00722592.

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GOG Reports on Evaluation of Pemetrexed in Treatment of Recurrent Platinum-Resistant Ovarian Cancer

A phase II Gynecologic Oncology Group (GOG) clinical study found that pemetrexed (Altima®)-an antifolate antineoplastic agent that disrupts folate-dependent cell replication metabolic processes-is sufficiently active in the treatment of recurrent platinum-resistant ovarian cancer to warrant further investigation.  “Thus [pemetrexed] should be considered for combination with other agents, especially carboplatin, in first-line therapy,” said David Miller, M.D., F.A.C.S. (University of Texas Southwestern Medical Center, Dallas, USA) and colleagues.

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David Miller, M.D. F.A.C.S., Professor, Gynecologic Oncology, University of Texas Southwestern Medical Center

A phase II Gynecologic Oncology Group (GOG) clinical study found that pemetrexed (Altima®)-an antifolate antineoplastic agent that disrupts folate-dependent cell replication metabolic processes-is sufficiently active in the treatment of recurrent platinum-resistant ovarian cancer to warrant further investigation.  “Thus [pemetrexed] should be considered for combination with other agents, especially carboplatin, in first-line therapy,” said David Miller, M.D., F.A.C.S. (University of Texas Southwestern Medical Center, Dallas, USA) and colleagues.

The purpose of the GOG study was to estimate the antitumor activity of pemetrexed in patients with persistent or recurrent, platinum-resistant epithelial ovarian or primary peritoneal cancer and to determine the nature and degree of toxicities.  The patients that participated in the study experienced disease progression on platinum-based primary chemotherapy or recurred within 6 months. Pemetrexed at a dose of 900 mg/m2 was administered as an intravenous infusion over 10 minutes every 21 days. Dose delay and adjustments were permitted for toxicity. Treatment was continued until disease progression or unacceptable adverse effects.  From July 6, 2004, to August 23, 2006, 51 patients enrolled in the study.  A total of 259 cycles (median, four; range one to 19 cycles) of pemetrexed were administered, with 40% of the patients receiving six or more cycles.

According to the investigators, the study produced the following results:

  • No treatment -related deaths were reported;
  • Eighteen patients (38%) had progressive disease. Three patients (6%) were not assessable;
  • One patient (2%) had a complete response (CR) and nine patients (19%) had partial responses (PRs), with a median duration response of 8.4 months. Seventeen patients (35%) had stable disease (SD) for a median of 4.1 months. Clinical benefit rate (CR + PR + SD) was 56%; and

Based upon the foregoing results, the investigators noted that pemetrexed “exhibited activity more favorable than that seen in other agents that have been test in first-line combinations by the GOG.” Pemetrexed, according to the investigators, has sufficient activity in the treatment of recurrent platinum-resistant ovarian cancer at the dose and schedule tested to warrant further investigation.

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NOV-002 and Carboplatin Slow Disease Progression of Platinum Drug Resistant Ovarian Cancer

Novelos Therapeutics, Inc. (OTCBB: NVLT), a biopharmaceutical company focused on the development of therapeutics to treat cancer and hepatitis, today announced continued encouraging results in an ongoing Massachusetts General Hospital Cancer Center and Dana-Farber/Harvard Cancer Center (DF/HCC) Phase 2 trial of NOV-002 in combination with carboplatin in platinum-resistant ovarian cancer patients. Fifteen patients have now been enrolled and, to date, 60% (9) have had slower than expected disease progression. NOV-002 was well-tolerated, further extending the excellent safety profile NOV-002 has demonstrated in previous studies. Detailed results of this trial will be presented as a poster at the 2008 annual meeting of the American Society of Clinical Oncology (ASCO) taking place May 30 – June 3 in Chicago, Illinois.

‘I am encouraged by these results in platinum-resistant ovarian cancer, with NOV-002 (in combination with carboplatin) apparently slowing disease progression in over half of the treated patients. Most women who have failed three lines of chemotherapy would be expected to progress in about eight weeks. I am excited to present the trial results at ASCO,’ said Dr. Carolyn Krasner, medical oncologist at the Massachusetts General Hospital Cancer Center and the Principal Investigator. ‘We look forward to working closely with Dr. Krasner, the Massachusetts General Hospital Cancer Center, Dana-Farber/Harvard and other institutions on designing and implementing a larger NOV-002 trial for this indication,’ said Harry Palmin, President and CEO of Novelos. ‘Our objective is to commence the next Phase 2 trial in platinum-resistant ovarian cancer in early 2009.’

According to the American Cancer Society, in 2007 approximately 22,000 U.S. women were diagnosed with ovarian cancer and 15,000 women were expected to die from it. There is a lack of effective treatment, particularly in the case of platinum-resistant patients. Once a woman’s ovarian cancer is defined as platinum-resistant the chance of having a partial or complete response to further platinum therapy is typically less than 10% and only 10-20% with other available agents. Thus, there is a major unmet medical need for this indication. …”

[Source: “Novelos Therapeutics Announces Continued Encouraging Results in Ongoing Phase 2 Ovarian Cancer Trial at Dan-Farber/Harvard Cancer Center;” Novelos Therapeutics, Inc. Press Release dated March 31, 2008.]

SNS-595 Shows Promise For Platinum-Resistant Ovarian Cancer Patients

Sunesis Pharmaceuticals, Inc. (Nasdaq: SNSS), a clinical-stage biopharmaceutical company focused on the discovery, development and commercialization of novel small-molecule therapeutics, announced positive interim data from the company’s ongoing Phase 2 clinical trial of its lead product candidate, SNS-595, in platinum-resistant ovarian cancer patients.

In this Phase 2 clinical trial, single agent SNS-595 has demonstrated disease control (defined as stable disease, partial response or complete response) in 31 of 35 patients evaluable for best response using GOG-RECIST criteria. Of these 31 patients, one patient had a complete response, four patients had partial responses (two unconfirmed) and 26 patients had a best response of stable disease. All patients enrolled in the trial have previously failed treatment with platinum-containing regimens, and fourteen of the 35 patients have also failed prior treatment with doxorubicin HCl liposome injection (Doxil(R)). Both platinum-resistant and Doxil-resistant patients in the Phase 2 clinical trial have responded to SNS-595 therapy.

‘Recurrence rates among ovarian cancer patients remain high, and the majority of refractory patients are resistant to platinum-based therapies. Based on these interim data, SNS-595 appears to be a promising, active agent in a difficult-to-treat ovarian cancer patient population,’ said William P. McGuire, M.D., Medical Director of the Harry and Jeanette Weinberg Cancer Institute at Franklin, and a lead investigator for the Phase 2 trial.

Among forty-five patients with sufficient follow-up to yield safety data, SNS-595 was generally well tolerated at a dose level of 48mg/m2 administered once every three weeks. The most common adverse events reported thus far include nausea, fatigue, vomiting and alopecia. There was a low rate of febrile neutropenia or other Grade 3/4 adverse events, and manageable Grade 1/2 nausea or vomiting.

Based on the indications of clinical activity and the acceptable tolerability profile demonstrated to date among this patient population, the dose of SNS-595 in this trial has been increased to 60 mg/m2 over twenty-eight days. Patient accrual at this dose level is ongoing.

‘We are pleased by the strong signal of activity emerging from our Phase 2 clinical trial of SNS-595 at the 48mg/m2 dose level. Based on the drug’s observed safety profile and recommendations from advisors, we are exploring a higher dose of SNS-595 in this trial. Enrollment has begun at 60 mg/m2 and we expect to enroll approximately 30 patients at this dose by the third quarter of this year,’ said Daniel C. Adelman, M.D., Senior Vice President, Development and Chief Medical Officer of Sunesis. ‘Enthusiasm for SNS-595 among our clinical investigators is growing and enrollment in this trial has been accelerating. We expect to present further data from this Phase 2 clinical trial this year.’

The interim clinical results are being presented in a poster, “A Phase 2 Trial of SNS-595 in Women with Platinum-Refractory Epithelial Ovarian Cancer” (Abstract # 290), at the 39th Annual Meeting on Women’s Cancer hosted by the Society of Gynecologic Oncologists (SGO) in Tampa, Fla. through March 12, 2008.”

About SNS-595

SNS-595 is a novel naphthyridine analog, structurally related to quinolones, a class of compounds which has not been used previously for the treatment of cancer. SNS-595 is a specific DNA intercalator and topoisomerase II poison, causing replication-dependent site-selective double strand DNA damage, irreversible G2 arrest and rapid apoptosis. In non-clinical evaluations, SNS-595 demonstrates broad and potent activity in xenograft, syngeneic and drug-resistant models. In addition to the Phase 2 clinical trial in ovarian cancer patients, SNS-595 is currently being evaluated in combination with cytarabine in a Phase 1b acute leukemia clinical trial. In clinical trials conducted to date, SNS-595 has been generally well tolerated and has shown objective responses in both solid and hematologic tumor types.”

Quoted Source: [“Sunesis Pharmaceuticals Reports Positive Interim Data for SNS-595 Single-Agent Activity in Platinum-Resistant Ovarian Cancer”, MedicalNewsToday.com, March 11, 2008. (Emphasis added by posting author)].

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