Shares in OncoSec Medical (NSDQ:ONCS) fell nearly -60% this morning after the company revealed preliminary data from its Phase IIb trial of intratumoral delivery of Tavo in people with unresectable, advanced melanoma.
OncoSec’s lead product, Tavo, uses electroporation to deliver IL-12 directly into a patient’s tumor, triggering an immune response.
As of Sept. 1, 21 people had enrolled in the Keynote-695 study. The is designed to assess the efficacy of Tavo with Merck‘s (NYSE:MRK) intravenous immunotherapy drug, Keytruda. People who enrolled in the trial had refractory, locally advanced or metastatic melanoma that progressed following treatment with Keytruda or Bristol-Myers Squibb‘s (NYSE:BMY) Opdivo product.
Out of the trial’s 21 patients, nine have completed 12 weeks of treatment and reached the first tumor evaluation point, according to OncoSec.
Two of the nine patients experienced a partial response, the company reported, and one patient had stable disease after 12 weeks.
“There is currently no approved therapy for the Keynote-695 patient population. A 10% response rate is considered meaningful in this cohort, since this is about what we expect with additional chemotherapy, however, such responses lack durability. The preliminary tumor responses (22% BORR and 33% DCR) and supporting immune data observed here for the first time are important,” lead investigator Dr. Adil Daud said in prepared remarks.
“Although several clinical studies have reported late-stage melanoma data in anti-PD-1 failures, such failures are inconsistently defined. This is a critical point,” Daud added. “Since patients in Keynote-695 have unequivocally failed approved anti-PD-1 therapies, these preliminary data, viewed in this context, carries weight.”
OncoSec said it expects the Keynote-695 study to wrap up in 2019, with a BLA submission planned for 2020.
ONCS shares were trading at 76¢ in early morning activity today, down -56%.