Positive Phase 2 data from Nektar Therapeutics' NKTR-102 study in women with platinum-resistant ovarian cancer

Nektar Therapeutics (Nasdaq: NKTR) today announced preliminary progression-free survival data from the first stage of a two-stage Phase 2 clinical study evaluating single-agent treatment with NKTR-102 in women with platinum-resistant ovarian cancer.  In the first stage of the study, 39 patients were enrolled with platinum-resistant disease and were evaluable for the secondary endpoint of progression-free survival (PFS).

The study showed that women who received NKTR-102 once every 21 days (q21 day) had a median PFS of 21.0 weeks.  In the second arm of the study, women who received NKTR-102 once every 14 days (q14 day) had a median PFS of 12.2 weeks.  Progression-free survival is a measure of how long patients live without their disease advancing.  Current agents approved by the U.S. Food & Drug Administration to treat women with platinum-resistant ovarian cancer have median PFS of between 9.1 and 13.6 weeks.

"NKTR-102 has demonstrated a progression-free survival time of nearly five months, which is remarkable for a largely refractory population that is expected to have a PFS of less than three months," said Lorianne Masuoka, M.D., Senior Vice President and Chief Medical Officer.  "With a confirmed objective GCIG response rate of 35 percent also in the every three week dose schedule and a favorable toxicity profile, NKTR-102 appears to offer great promise to women with chemo-resistant ovarian cancer.  We look forward to sharing additional data when all patients have concluded both stages of the study."

77% of the 39 women in the first stage of the NKTR-102 Phase 2 study had progressed within three months of their last platinum dose and 44% of patients in the first stage had actually progressed within three weeks of their last platinum regimen. There are patients in the first stage of the study still receiving treatment with NKTR-102.

In January, Nektar reported initial data from the first stage of the Phase 2 study for the primary endpoint of overall response rate using Gynecologic Cancer InterGroup (GCIG) criteria, i.e., a combination of response by tumor imaging (RECIST) and/or ovarian cancer biomarker (CA-125) criteria.(2) Women in the first stage of the study showed an overall GCIG response rate of 32% (6/19) in the once every 14 days (q14 day) dose schedule and 35% (7/20) for the once every 21 days (q21 day) dose schedule.  Confirmed objective response rates using RECIST were 21% (4/19) and 22% (4/18) for the q14 day and q21 day dose schedules, respectively.  CA-125 response rates were 31% (5/16) and 38% (6/16), for the q14 day and q21 day dose schedules, respectively.  

The most commonly observed grade 3 or grade 4 side effects in the study to date (every 14 day/every 21 day dose schedule) were diarrhea (29%/10%) and neutropenia (14%/10%).

The Phase 2 study has now completed enrollment with a total of 71 patients treated. The study is ongoing.  Full data are expected to be presented at a major scientific conference in 2010.

SOURCE Nektar Therapeutics