September 15, 2008
Pfizer Oncology Presents Safety and Efficacy Results Of CP-751,871 Study At ESMO 2008
Pfizer announced today updated safety and efficacy results surrounding its investigational compound, CP-751,871, in patients with non-small cell lung cancer (NSCLC). These results, along with supporting correlative science data, were presented at the 33rd European Society for Medical Oncology (ESMO) congress in Stockholm, Sweden.
Results from a Phase II, randomized, non-comparative study, "Addition of CP-751,871, an anti-IGF-1R antibody, to paclitaxel and carboplatin results in high activity in NSCLC, particularly in squamous subtype," (abstract 229PD) showed 54 percent of patients with Stage III/IV treatment-naive NSCLC receiving the combination CP-751,871 plus carboplatin and paclitaxel (n=97) experienced objective responses. The response rate was 41 percent in patients treated with carboplatin and paclitaxel alone (n=53).In addition, 78 percent of a subset of patients with squamous cell carcinoma (n=9) and 57 percent of a subset of patients with adenocarcinoma (n=28) receiving 20 mg/kg of CP-751,871 plus carboplatin and paclitaxel experienced objective responses. Response rates were 46 percent and 25 percent, respectively, for squamous cell (n=12) and adenocarcinoma patients (n=20) receiving carboplatin and paclitaxel alone. No response advantage with CP-751,871 was seen in a subset of patients with undifferentiated tumors (Not Otherwise Specified, NOS).
"These data contribute to our evolving understanding of the potential safety and efficacy of CP-751,871 in patients with NSCLC, a devastating disease -- an estimated 1.5 million new cases are expected worldwide this year - with limited treatment options," said study presenter Luis Paz-Ares, M.D., Chief, Division of Medical Oncology, Virgen del Rocio University Hospital, Seville, Spain.
Patients who received CP-751,871 20 mg/kg showed the greatest improvement in progression-free survival (PFS). PFS was defined as either the length of time before the cancer progressed or death.
Twenty of the 53 patients in the carboplatin and paclitaxel arm crossed over to receive CP-751,871. Without censoring for crossover, the median PFS in patients receiving no CP-751,871, 10 and 20 mg/kg of CP-751,871 plus carboplatin and paclitaxel was, respectively, 4.3, 3.6 and 5 months. The median PFS in squamous cell patients receiving 20 mg/kg of CP-751,871 plus carboplatin and paclitaxel was 5.6 months (4.3 months for patients with squamous cell cancer treated with carboplatin and paclitaxel alone).
After censoring for crossover, median PFS in patients receiving no CP-751,871, 10 and 20 mg/kg of CP-751,871 plus carboplatin and paclitaxel was, respectively, 3.5, 3.6 and 5 months.
The side effects of CP-751,871 were generally manageable. The most common Grade 3 or 4 side effects reported in this study were fatigue (10 percent), hyperglycemia (increased blood sugar) (20 percent) and neutropenia (30 percent).
Additional study results presented by Antonio Gualberto, M.D., Ph.D., Director and Global Clinical Leader (Oncology), Pfizer Global Research and Development, New London, CT, at the meeting expand the understanding of the relationship between IGF-1R inhibition and the activity in different populations of NSCLC patients. Results of the correlative science study, "IGF-1R markers in NSCLC patients on anti-IGF-1R therapy," (abstract 1320) conducted to investigate the molecular composition of lung tumours and its relevance to anti-IGF-1R therapy showed that members of the IGF-1R pathway appear to be expressed differentially across lung tumor histologies, which may explain the differential activity of CP-751,871 across these histologies.
"These data provide greater insight into the potential relationship between tumor histology and response to CP-751,871 observed in the clinical studies," said Dr. Gualberto. "Furthermore, the results support the global Phase III clinical trial program for CP-751,871 in NSCLC."
CP-751,871, a fully human monoclonal antibody, is a highly specific inhibitor of the IGF-1R pathway. The IGF-1R pathway is one of the key signaling pathways in cancer cells that lead to uncontrolled growth and survival of tumour cells.
Pfizer has a global Phase III clinical trial registration program for CP-751,871 in NSCLC underway. The program initially includes two studies in patients with non-adenocarcinoma NSCLC: ADVIGO 1016 in first-line patients and ADVIGO 1018 in refractory patients. In addition, Pfizer is studying CP-751,871 in clinical trials for the potential treatment of many other cancers, including prostate, breast and colon cancers and Ewing's sarcoma. To date, more than 700 patients have participated in CP-751,871 clinical trials in multiple tumor types.
For more information on the ADVIGO registration program please visit, http://PfizerCancerTrials.com.
About Pfizer Oncology
Pfizer Oncology is committed to the discovery, investigation and development of treatments and currently has 22 innovative compounds in clinical development across four platforms. By leveraging the strength of our resources and scientific talent, Pfizer Oncology strives to discover and develop novel treatment options to improve the outlook for oncology patients. Pfizer currently devotes more than 22 percent of its total R&D budget to the field of oncology, investing annually in worldwide research initiatives. We also partner with healthcare providers, governments and local communities around the world to provide better quality healthcare and health system support.
For more information, please visit http://www.Pfizer.com.
DISCLOSURE NOTICE: The information contained in this release is as of September 15, 2008. Pfizer assumes no obligation to update any forward-looking statements contained in this release as the result of new information or future events or developments.
This release contains forward-looking information about a product candidate, CP-751,871, including with respect to potential indications, that involves substantial risks and uncertainties. Such risks and uncertainties include, among other things, the uncertainties inherent in research and development; decisions by regulatory authorities regarding whether and when to approve any drug applications that may be filed for any such indications as well as their decisions regarding labeling and other matters that could affect the availability or commercial potential of any such indications; and competitive developments.
A further description of risks and uncertainties can be found in Pfizer's Annual Report on Form 10-K for the fiscal year ended December 31, 2007 and in its reports on Form 10-Q and Form 8-K.