Progenics initiates Phase I prostate cancer study

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 prostate-specific membrane antigen (PSMA) antibody-drug conjugate (ADC) followed by the option to continue therapy for a total of 12 months.

The Phase I, 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 and circulating tumor cell 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.

PSMA ADC is said to be 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.

Paul Maddon, founder and CEO of Progenics Pharmaceuticals, said: “In pre-clinical studies, PSMA ADC has exhibited a high level of tumor-specific activity. 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.”