TRACON Pharmaceuticals Inc (NASDAQ:TCON) revealed that its PD-L1 antibody envafolimab achieved positive results based on the double-digit Objective Response Rate (ORR) assessed by a blinded independent central review in its ongoing multicenter ENVASARC Phase 2 pivotal trial in patients with Undifferentiated Pleomorphic Sarcoma (UPS) or Myxofibrosarcoma (MFS) cancers.
According to TRACON, the independent data monitoring committee (IDMC) for the ongoing ENVASARC Phase 2 pivotal trial recommended "continued accrual as planned in both cohorts: single agent envafolimab and envafolimab in combination with Yervoy (ipilimumab)."
The San Diego company, which utilizes a capital-efficient product development platform to develop its clinical-stage pipeline of cancer therapies, said IDMC reviewed interim safety and efficacy data from 18 patients enrolled in each cohort, who completed a minimum of 12 weeks of efficacy evaluations (two on-treatment scans).
READ: TRACON Pharmaceuticals doses first patient in drug trial to treat malignant tumours
The double-digit ORR assessed by a blinded independent central review in each cohort more than satisfied the prespecified futility rule, said the company. Envafolimab monotherapy and in combination with Yervoy was well tolerated, with only a single related serious adverse event reported in 36 patients.
The company said that the responses were noted in patients regardless of weight at the 600 milligrams (mg) dose of envafolimab that was instituted following the previous IDMC review of interim safety and efficacy data from patients in the ENVASARC trial treated at the 300 mg dose of envafolimab.
Positive milestone
“We are pleased with the activity of the 600 mg dose of envafolimab that has demonstrated a double-digit objective response rate both as a single agent and in combination with Yervoy, even at this early 12-week time point,” TRACON chief medical officer James Freddo said in a statement.
“We are also encouraged with the safety data showing that envafolimab monotherapy and in combination with Yervoy are well tolerated. This interim analysis is a positive milestone, and we look forward to the next interim analysis which will be conducted after the 46th patient in each cohort has completed a minimum of 12 weeks of efficacy evaluations," he added.
The clinical-stage biopharma company noted that “enrollment continues ahead of schedule” and the next interim analysis is expected in mid-2023 with full enrollment now expected before the end of 2023.
“Importantly, accrual in ENVASARC remains ahead of projections and we are excited by the emerging data and for envafolimab’s potential to become a differentiated treatment for sarcoma patients,” said Freddo.
Envafolimab (KN035), a single-domain antibody against PD-L1 invented by Alphamab Oncology and licensed by TRACON, is the first approved subcutaneously injected PD-(L)1 inhibitor. In September 2022, TRACON received fast-track designation from the US Food and Drug Administration (FDA) for envafolimab for patients with locally advanced, metastatic undifferentiated pleomorphic sarcoma and myxofibrosarcoma who have progressed on one or two prior lines of chemotherapy.
“Achieving a double-digit ORR with a well-tolerated safety profile, as both monotherapy and in combination, positions envafolimab to become a potential treatment option for patients with refractory undifferentiated pleomorphic sarcoma (UPS) and myxofibrosarcoma (MFS). The sole approved treatment for these patients is Votrient, which achieved a 4% ORR and carries a black box warning for fatal liver toxicity," said TRACON CEO Charles Theuer.
Contact the author Uttara Choudhury at uttara@proactiveinvestors.com
Follow her on Twitter: @UttaraProactive