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PGNX starts Ph I prostate cancer trial

Progenics Initiates Phase 1 Clinical Study of Targeted Therapy for Prostate Cancer
Monday September 8, 7:00 am ET
Monoclonal Antibody-Drug Conjugate Selectively Targets Cancer Cells

TARRYTOWN, N.Y.--(BUSINESS WIRE)--Progenics Pharmaceuticals, Inc. (Nasdaq: PGNX - News) today announced the initiation of a phase 1 dose-escalation clinical study of its prostate-specific membrane antigen (PSMA) antibody-drug conjugate (ADC). PSMA ADC is an investigational therapy that combines a prostate-cancer antibody with a cancer drug. Unlike traditional chemotherapy, PSMA ADC is designed to deliver the drug selectively to prostate cancer cells by targeting a surface protein, PSMA. The clinical study will include patients with progressive, metastatic, hormone-refractory disease following prior taxane chemotherapy, and will assess the safety, tolerability and initial clinical activity of PSMA ADC followed by the option to continue therapy for a total of 12 months.

“In pre-clinical studies, PSMA ADC has exhibited a high level of tumor-specific activity,” said Paul J. Maddon, M.D., Ph.D., Progenics Pharmaceuticals’ Founder, Chief Executive Officer and Chief Science Officer. “Now, our first-in-man clinical studies will assess initial anti-tumor activity in patients after 12 weeks and subsequently, with an optional follow-up period, provide up to one year of dosing information.”

Antibody-drug conjugate therapy

PSMA ADC is an antibody-drug conjugate that consists of a fully human monoclonal antibody that binds PSMA and is linked to a highly potent cancer drug, a derivative of auristatin.

The monoclonal antibody portion of PSMA ADC selectively targets PSMA, a protein that is abundantly expressed on the surface of prostate cancer cells. Using technology licensed from Seattle Genetics, Inc. (Nasdaq: SGEN - News), the fully human PSMA antibody is linked to a potent derivative of auristatin, a cancer drug that inhibits cell proliferation by disrupting the cellular “backbone” (i.e., microtubules) required for replication. The resultant antibody-drug conjugate attaches to the PSMA protein on the surface of prostate cancer cells and is designed to:

* internalize the antibody-drug conjugate into the cancer cell;
* release and thereby activate the cancer drug; and
* destroy the malignant cell.

The cancer drug is chemically linked to the antibody and is designed to activate only after the antibody recognizes a cancer cell.

Two-stage clinical study design

The phase 1, open-label, dose-escalation clinical trial will include as many as 40 men with progressive, hormone-refractory prostate cancer, and who had prior therapy with taxane chemotherapy drugs. The study will investigate the duration of clinical benefit derived from PSMA ADC treatment while also assessing the drug’s safety and tolerability. The initial 12-week period will evaluate up to four intravenous doses of PSMA ADC over five dose levels, administered at three-week intervals. The study will include evaluations of pharmacodynamics, radiographic changes in tumor burden, and changes in prostate-specific antigen (PSA) and circulating tumor cell (CTC) values compared to baseline.

Following the 12-week period, patients will be offered, at their physician’s discretion, the option to continue treatment for an additional 39 weeks with the same dose of PSMA ADC as administered in their initial cohort. Qualified subjects will receive up to 13 additional doses of study drug at three-week intervals.


http://biz.yahoo.com/bw/080908/20080908005469.html?.v=1