Bicara Therapeutics has unveiled updated data for its bifunctional antibody paired with Keytruda in head and neck squamous cell carcinoma (HNSCC), including a first look at overall survival (OS) data for HPV-negative patients as the biotech enrolls for a pivotal trial in the indication.
In the phase 1/1b trial, the two-year OS rate was 46%, and median OS was 21.3 months for 28 HPV-negative patients, according to data shared at this year’s American Society of Clinical Oncology conference in Chicago. The biotech is also holding a conference call regarding the data Sunday.
The study is evaluating Bicara’s ficerafusp alfa and Keytruda among patients with first-line, PD-L1-positive recurrent or metastatic HNSCC.
In the HPV-negative subset, the confirmed objective response rate (ORR) was 54%, with an additional three (10%) unconfirmed responses. Six patients, or 21% of the group, recorded complete responses.
Among the 15 patients with confirmed ORRs, 12 had at least 80% tumor shrinkage. For the same group, median duration of response (mDOR) was 21.7 months.
The company previously reported an overall response rate (ORR) of 54% for 39 patients in the ongoing phase 1/1b, which includes confirmed and unconfirmed responses.
For all patients in the trial, median progress free survival (PFS) was 7.4 months. The median PFS rose to 9.8 months for the HPV-negative subgroup.
The company has deemed the findings for the HPV-negative cohort as “deep and durable,” in a June 1 release, noting that the safety profile is “manageable” and consistent with previously reported adverse events.
“These latest phase 1/1b data are impressive, particularly the duration of response, which represents a significant advance over historical controls in patients with HPV-negative recurrent/metastatic head and neck squamous cell carcinoma, including anti-PD-1 combinations with chemotherapy or EGFR inhibitors,” Christine Chung, M.D., chair of the department of head and neck-endocrine oncology and deputy physician-in-chief at the Moffitt Cancer Center, said in Bicara’s June 1 release. “This reflects the enhanced ability of ficerafusp alfa to remodel the tumor microenvironment allowing the tumor penetration of immune cells required for deep and durable responses in these patients.
“In addition, the prolonged overall survival, highlighted by a median OS of 21.3 months, reinforces the potential of ficerafusp alfa to address a critical unmet need by delivering durable anti-tumor responses and meaningful improvements in patients’ quality of life,” Chung added.
Ficerafusp alfa is made to target both EGFR and TGF-β. Bicara CEO Claire Mazumdar, Ph.D., has previously credited the biotech’s $362 million IPO last September to a syndicate of investors who believe in the asset.
After Bicara reported a 12-month OS of 61% for its HPV-negative population last week, biotech Merus shared that its bispecific targeting EGFR and LGR5 had a 79% 12-month survival rate in PD-L1-positive recurrent or metastatic head and neck squamous cell carcinoma. William Blair analysts said the Merus candidate has a “best-in-disease profile."
The Merus data sent Bicara’s stock tumbling and it has yet to recover, down 37% in the last month. The biotech is currently enrolling for a pivotal phase 2/3 trial assessing ficerafusp alfa, with an expected enrollment of 650 patients.