Immunomedics Reports Final Survival Data From Two-Part Pancreatic Cancer Study With Yttrium-90-Labeled Clivatuzumab Tetraxetan Combined With Gemcitabine

Immunomedics, Inc.

today announced that repeated cycles of small doses of its proprietary humanized antibody, clivatuzumab tetraxetan, labeled with yttrium-90 (90Y) and given in combination with gemcitabine, when compared with single cycle only, extended survival in patients with advanced, inoperable, pancreatic cancer. A total of 100 patients with previously untreated Stage III or IV pancreatic cancer were enrolled into this 2-part, open-label, multicenter study. Forty-two patients were enrolled into Part I, of which 38 patients completed their treatment of 90Y-clivatuzumab tetraxetan at 6.5, 9, 12 or 15 mCi/m2 x 3, and a low, fixed gemcitabine dose of 200 mg/m2 x 4. Thirteen patients were retreated with the same cycle 1 - 3 times. In Part II, 58 patients were enrolled to receive 3 weekly 90Y doses of 12 mCi/m2 and gemcitabine doses at 200, 600 or 1000 mg/m2 x 4. Fifty-two patients completed this treatment combination with 18 patients receiving repeated therapy cycles at the same gemcitabine dose but 90Y doses of 6.5, 9 or 12 mCi/m2. Although Part I and Part II are different, the combined median overall survival (OS) for the 31 patients who had received multiple cycles was 9.3 months, which compares favorably with other regimens for advanced pancreatic cancer. Separately, patients receiving multiple cycles in Part I reported a median OS of 11.8 months, compared with 5.4 months for single cycle only patients. A similar pattern was seen in Part II, with median OS of 8.7 months vs. 4.2 months for multiple and single cycle, respectively. The overall disease control rates, which include complete response, partial response and stable disease, by CT-based RECIST criteria,