Bicara Therapeutics’ Preliminary Phase 1b Expansion Cohort Data Evaluating 750mg of Ficerafusp Alfa Weekly Plus Pembrolizumab Advances Pivotal Study Dose Selection on Track for First Quarter 2026

Rhea-AI Summary

Bicara Therapeutics (Nasdaq: BCAX) presented preliminary Phase 1b expansion data for ficerafusp alfa 750mg QW plus pembrolizumab in 1L HPV-negative R/M HNSCC on Dec 6, 2025.

Key metrics: 57% confirmed overall response rate, 10% complete responses, and 29% of responders with ≥80% tumor shrinkage at preliminary follow-up. Biomarker comparisons show 1500mg yields greater intratumoral TGF-β inhibition, higher immune activation, and deeper responses (median depth 82% vs 63%). Company expects to declare the pivotal FORTIFI-HN01 optimal dose in Q1 2026.

Positive

• 57% confirmed overall response rate at 750mg
• 10% complete response rate at 750mg
• 29% of responders achieved ≥80% tumor shrinkage
• 1500mg showed greater TGF-β inhibition and immune activation
• Median depth of response 82% at 1500mg vs 63% at 750mg

Negative

• Data based on preliminary duration of follow-up
• 750mg produced lower median depth of response (63%) versus 1500mg (82%)
• Optimal biologic dose not yet declared; decision expected in Q1 2026

Key Figures

Dose level 750 mg weekly Ficerafusp alfa plus pembrolizumab Phase 1b expansion cohort

Dose level 1500 mg weekly Higher-dose ficerafusp alfa cohort biomarker comparison

Confirmed overall response rate 57% 750 mg ficerafusp alfa + pembrolizumab in 1L HPV-negative R/M HNSCC

Complete response rate 10% Patients achieving complete response at 750 mg dose

Deep response rate 29% Responders with ≥80% tumor shrinkage at 750 mg dose

Median depth of response 82% 1500 mg dose at 24 weeks

Median depth of response 63% 750 mg dose at 24 weeks

Deep responders at 1500 mg 64% Responders achieving deep response at higher dose

Market Reality Check

$18.20 Last Close

Volume Volume 701,925 is slightly above the 20-day average of 652,151 (relative volume 1.08). normal

Technical Shares at $18.20 are trading above the 200-day MA of $13.04 but about 19.74% below the 52-week high.

Peers on Argus 1 Up

Peers in Biotechnology show mixed moves: TYRA -3.63%, ANAB +1.72%, PVLA +4.68%, RIGL +2.84%, TERN +5.88%. Momentum scanner only flagged DAWN up 4.17%, suggesting BCAX’s move is stock-specific rather than a sector-wide shift.

Historical Context

Date	Event	Sentiment	Move	Catalyst
Dec 01	Clinical data update	Positive	-6.6%	Publication of Phase 1b 750mg cohort abstract and ESMO Asia presentation plan.
Nov 10	Earnings & update	Positive	-4.8%	Q3 results, strong cash runway and confirmation of FDA Breakthrough Therapy Designation.
Oct 13	Regulatory designation	Positive	+4.1%	FDA Breakthrough Therapy Designation for ficerafusp alfa plus pembrolizumab in 1L HNSCC.
Aug 27	Investor conferences	Neutral	-0.9%	Announcement of participation in multiple September healthcare investor conferences.
Aug 12	Earnings & trial data	Positive	+4.8%	Q2 results and strong Phase 1/1b efficacy data for ficerafusp alfa in HNSCC.

Pattern Detected

Recent positive clinical and business updates have sometimes seen negative price reactions, with two of the last three upbeat data/earnings events followed by notable sell-offs.

Recent Company History

Over the last six months, Bicara has steadily advanced ficerafusp alfa toward pivotal development. On Aug 12, it reported Q2 2025 results citing strong Phase 1/1b data and a robust cash position. Subsequent conferences on Aug 27 maintained visibility. A key inflection came on Oct 13 when the FDA granted Breakthrough Therapy Designation based on earlier cohorts. Q3 results on Nov 10 reiterated long cash runway but drew a negative reaction. On Dec 01, publication of the 750mg cohort abstract for ESMO Asia again coincided with a sell-off, framing today’s fuller ESMO data as part of an ongoing dose-optimization narrative.

Regulatory & Risk Context

Active S-3 Shelf Registration 2025-10-03

Bicara has an active Form S-3 shelf filed on 2025-10-03, effective through 2028-10-03, and has already used it once via a 424B5 prospectus supplement. The shelf, together with the disclosed at-the-market program in recent filings, provides capacity to issue additional securities, which can be a source of future financing and potential dilution.

Market Pulse Summary

This announcement details preliminary Phase 1b data showing a 57% confirmed overall response rate at 750 mg and deeper responses at 1500 mg, supporting dose selection for the pivotal FORTIFI-HN01 trial. It follows earlier Breakthrough Therapy Designation and prior ESMO abstract disclosure, extending a consistent efficacy story. Investors may watch for the planned optimal dose declaration in Q1 2026, further biomarker analyses, and how these choices interact with existing financing tools disclosed in recent SEC filings.

Key Terms

phase 1b medical

"presented preliminary data from a Phase 1b expansion cohort evaluating 750 mg"

"Phase 1b" is an early stage in testing a new medical treatment or vaccine, where it is given to a small group of people to evaluate its safety and determine the right dose. For investors, this phase signals progress in development, indicating the treatment is advancing through initial safety checks, which can influence expectations for future success and potential market impact.

overall response rate medical

"750 mg of ficerafusp alfa demonstrated a 57% confirmed overall response rate"

Overall response rate is the percentage of patients in a clinical study whose measurable disease shrinks or disappears after receiving a treatment. Investors watch it like a product’s “hit rate” because higher response rates can signal a drug’s effectiveness, boost chances of regulatory approval and market demand, and affect a company’s future revenue prospects, similar to how a higher batting average suggests a more reliable player.

pembrolizumab medical

"750 mg of ficerafusp alfa weekly (QW) in combination with pembrolizumab in first-line"

A cancer immunotherapy drug that helps the body’s immune system recognize and attack tumor cells by blocking a molecular “brake” that tumors use to hide. Investors watch it because regulatory approvals, clinical trial results, dosing rules, and competition directly affect potential sales, profit forecasts, and the valuation of companies that sell or license the drug—think of trial outcomes as checkpoint signs that can open or close a revenue road.

head and neck squamous cell carcinoma medical

"HPV-negative recurrent/metastatic (R/M) head and neck squamous cell carcinoma (HNSCC)"

A type of cancer that starts in the thin, flat cells that line the mouth, throat, voice box and upper airway; imagine the lining like roof shingles that, when damaged, can grow into a harmful lump. It matters to investors because its diagnosis, treatment options and regulatory approvals drive demand for drugs, tests and therapies—affecting clinical trial outcomes, market size, company valuations and the financial risk/reward of healthcare investments.

tumor microenvironment medical

"yielded a greater increase TGF-β inhibition within the tumor microenvironment and greater immune"

The tumor microenvironment is the immediate area surrounding a cancer cell, made up of nearby cells, blood vessels, and support structures that influence how the cancer grows and spreads. It functions like a bustling neighborhood that can either help or hinder the tumor’s development. For investors, understanding changes in this environment can signal the effectiveness of treatments and potential shifts in a cancer-related market.

biomarker medical

"New biomarker data to be presented during Bicara’s corporate call and webcast show that"

A biomarker is a measurable indicator found in the body, such as in blood or tissues, that provides information about health, disease, or how the body responds to treatment. For investors, biomarkers can signal the potential success or risk of medical products or therapies, influencing the value of related companies and industry trends. They act like signals or clues that help assess the progress of medical advancements and their market impact.

tGF-β inhibition medical

"greater TGF-β inhibition, observed at 1500mg of ficerafusp alfa, drives deeper tumor"

TGF‑β inhibition is the deliberate blocking of transforming growth factor‑beta, a naturally occurring protein that helps regulate cell growth, immune behavior and scar formation. For investors, drugs that inhibit TGF‑β can change the course of diseases such as certain cancers, fibrosis and immune disorders, so progress or setbacks in these programs can have large impacts on a biotech company's value, much like a breakthrough or failure in a disruptive technology.

complete response medical

"57% confirmed overall response rate, with 10% of patients achieving a completed response"

A complete response is a positive outcome in which a company’s efforts to address issues or questions fully resolve the problem, often meaning that no further action or investigation is needed. For investors, it signals that concerns have been thoroughly addressed, which can boost confidence in the company's stability or decision-making. Think of it like a doctor fully treating an illness, leaving no remaining symptoms.

AI-generated analysis. Not financial advice.

Ficerafusp alfa 750mg QW in combination with pembrolizumab demonstrates consistent overall response rate and safety profile comparable to 1500mg QW dose, further derisking pivotal FORTIFI-HN01 study interim analysis

Totality of data demonstrates that greater TGF-β inhibition, observed at 1500mg of ficerafusp alfa, drives deeper tumor responses that translate to more durable outcomes for patients

Pivotal FORTIFI-HN01 optimal dose declaration expected in first quarter 2026

Company to host conference call and webcast today at 9:00 a.m. ET

BOSTON, Dec. 06, 2025 (GLOBE NEWSWIRE) --  Bicara Therapeutics Inc. (Nasdaq: BCAX), a clinical-stage biopharmaceutical company committed to bringing transformative bifunctional therapies to patients with solid tumors, today presented preliminary data from a Phase 1b expansion cohort evaluating 750 mg of ficerafusp alfa weekly (QW) in combination with pembrolizumab in first-line (1L) human papillomavirus (HPV)-negative recurrent/metastatic (R/M) head and neck squamous cell carcinoma (HNSCC). The data were highlighted in an oral presentation by Deborah Wong, MD, PhD of UCLA Medical Center at the European Society for Medical Oncology (ESMO) Asia Congress and will be discussed on a company conference call and webcast today, December 6, at 9:00 a.m. ET.

“Inadequate tumor penetration remains a major barrier in treating solid tumors such as R/M HNSCC,” said Claire Mazumdar, PhD, MBA, Chief Executive Officer of Bicara Therapeutics. “Ficerafusp alfa, the first and only bifunctional EGFR-directed antibody x TGF-β ligand trap, was purposefully designed to deliver deep and durable responses with the potential to meaningfully extend overall survival for patients. The data presented today mark an important advancement in our dose-optimization strategy, reinforce our confidence in the interim overall response rate analysis as the foundation for pursuing accelerated approval in the FORTIFI-HN01 pivotal trial, and further elucidate the relative contribution of TGF- β in driving deep and durable tumor responses. We have made significant progress in the FORTIFI-HN01 trial this year and are on track to declare an optimal dose in the first quarter of 2026.”

Phase 1/1b expansion cohort data presented at ESMO Asia show that 750mg ficerafusp alfa in combination with pembrolizumab was generally well-tolerated, with a safety profile consistent with the known safety profile of ficerafusp alfa plus pembrolizumab in R/M HNSCC. At a preliminary duration of follow-up, 750 mg of ficerafusp alfa demonstrated a 57% confirmed overall response rate, with 10% of patients achieving a completed response, and 29% of responders demonstrating deep responses of at least 80% tumor shrinkage.

New biomarker data to be presented during Bicara’s corporate call and webcast show that 1500mg of ficerafusp alfa yielded a greater increase TGF-β inhibition within the tumor microenvironment and greater immune activation, compared to 750mg of ficerafusp alfa. The increased TGF-β inhibition in the tumor translated to greater depth of clinical responses at 24 weeks. The median depth of response was 82% at the 1500mg dose vs. 63% at the 750mg dose, and 64% of responders at 1500mg achieved a deep response, compared to 27% of responders at the 750mg dose.

The totality of the data suggests that a higher dose of ficerafusp alfa with greater TGF-β inhibition and immune activation drives deeper tumor responses that translate to more durable outcomes for patients.

Bicara plans to declare the optimal biologic dose for use in the pivotal FORTIFI-HN01 study in the first quarter of 2026.

Conference Call and Webcast Details
Bicara Therapeutics will host a conference call and webcast today December 6, 2025 at 9:00 a.m. ET. Individuals may register for the conference call by clicking the link here. Once registered, participants will receive dial-in details and a unique PIN which will allow them to access the call. An audio webcast will be accessible through the Investor Relations section of Bicara’s website under Events and Presentations. An archived replay will also be available for 30 days following the webcast.

About Head and Neck Squamous Cell Carcinoma
Head and neck squamous cell carcinomas (HNSCCs) develop from the mucosal epithelium in the oral cavity, pharynx and larynx and are the most common malignancies that arise in the head and neck. HNSCC is one of the most common cancers in the United States and globally with a rising incidence anticipated to reach one million new global cases annually by 2030. Ten percent of HNSCC patients are diagnosed with metastatic disease and up to 30% develop a recurrence or metastases over time after receiving initial treatment for advanced HNSCC.

Most cases of HNSCC are thought to result from accumulated mutations caused by carcinogenic exposures such as tobacco smoke or HPV infection. Approximately 80% of patients with R/M HNSCC are HPV-negative. These HPV-negative tumors often exhibit a recurrence pattern that is primarily local and are associated with severe morbidities, including fatal tumor bleeding, intense pain, difficulty swallowing, significant weight loss, and cachexia. This highlights a critical unmet need for therapies that have the potential to deliver durable anti-tumor responses, ultimately leading to meaningful improvements in patients' quality of life.

About Ficerafusp Alfa
Ficerafusp alfa is a first-in-class bifunctional antibody designed to drive tumor penetration by breaking barriers in the tumor microenvironment that have challenged the treatment of multiple solid tumor cancers. Specifically, ficerafusp alfa combines two clinically validated targets: an epidermal growth factor receptor (EGFR) directed monoclonal antibody with a domain that binds to human transforming growth factor beta (TGF-β). Through this targeted mechanism, ficerafusp alfa reverses the fibrotic and immune-excluded tumor microenvironment driven by TGF-β signaling to enable tumor penetration that drives deep and durable responses. The U.S. Food and Drug Administration (FDA) has granted Breakthrough Therapy Designation to ficerafusp alfa in combination with pembrolizumab for the first line (1L) treatment of patients with metastatic or with unresectable, recurrent (R/M) head and neck squamous cell carcinoma (HNSCC) whose tumors express programmed death-ligand 1 with combined positive score (CPS) ≥1, excluding human papillomavirus (HPV)-positive oropharyngeal squamous cell carcinoma.

Ficerafusp alfa is currently being evaluated in FORTIFI-HN01, a pivotal Phase 2/3 clinical trial in patients with 1L R/M HNSCC.

About Bicara Therapeutics
Bicara Therapeutics is a clinical-stage biopharmaceutical company committed to bringing transformative bifunctional therapies to patients with solid tumors. Bicara’s lead program, ficerafusp alfa, is a first-in-class bifunctional antibody designed to drive tumor penetration by breaking barriers in the tumor microenvironment that have challenged the treatment of multiple solid tumor cancers. Specifically, ficerafusp alfa combines two clinically validated targets: an epidermal growth factor receptor (EGFR) directed monoclonal antibody with a domain that binds to human transforming growth factor beta (TGF-β). Through this targeted mechanism, ficerafusp alfa reverses the fibrotic and immune-excluded tumor microenvironment driven by TGF-β signaling to enable tumor penetration that drives deep and durable responses. Ficerafusp alfa is being developed in head and neck squamous cell carcinoma, where there remains a significant unmet need, as well as other solid tumor types. For more information, please visit www.bicara.com or follow us on LinkedIn and X.

Forward-Looking Statements
This press release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, as amended. These statements may be identified by words such as “may,” “might,” “will,” “could,” “would,” “should,” “plan,” “anticipate,” “intend,” “believe,” “expect,” “estimate,” “seek,” “predict,” “future,” “project,” “potential,” “continue,” “target” and similar words or expressions, or the negative thereof, are intended to identify forward-looking statements, although not all contain identifying words. Any statements in this press release that are not statements of historical fact may be deemed to be forward-looking statements. These forward-looking statements include, without limitation, express or implied statements regarding Bicara’s clinical development of ficerafusp alfa in combination with pembrolizumab and presentation of early data from a Phase 1b expansion cohort evaluating 750 mg of ficerafusp alfa weekly (QW) in combination with pembrolizumab in first-line (1L) human papillomavirus (HPV)-negative recurrent/metastatic (R/M) head and neck squamous cell carcinoma (HNSCC), the expected therapeutic potential and clinical benefits of ficerafusp alfa, including potential efficacy and tolerability, and Bicara’s optimal biological dose selection plans. Any forward-looking statements in this press release are based on management's current expectations and beliefs and are subject to a number of risks and uncertainties that are difficult to predict. Factors that could cause actual results to differ include, but are not limited to, risks and uncertainties related to uncertainties inherent in the development of product candidates, including the conduct of research activities and the conduct of clinical trials; uncertainties as to the availability and timing of results and data from clinical trials; whether results from prior preclinical studies, preliminary or interim data from earlier stage clinical trials will be predictive of the results of subsequent preclinical studies and clinical trials; regulatory developments in the United States and foreign countries; whether Bicara’s cash resources will be sufficient to fund its foreseeable and unforeseeable operating expenses and capital expenditure requirements; as well as the risks and uncertainties identified in Bicara’s filings with the Securities and Exchange Commission (SEC), including its Annual Report on Form 10-K for the year ended December 31, 2024, its Quarterly Report on Form 10-Q for the quarter ended September 30, 2025 and any subsequent filings Bicara makes with the SEC. In addition, any forward-looking statements represent Bicara’s views only as of today and should not be relied upon as representing its views as of any subsequent date. Bicara explicitly disclaims any obligation to update any forward-looking statements. No representations or warranties (expressed or implied) are made about the accuracy of any such forward-looking statements.

Contacts

Investors
Jenna Cohen
IR@bicara.com

Media
Amanda Lazaro
1AB
Amanda@1abmedia.com

FAQ

What were the confirmed response rates for BCAX ficerafusp alfa 750mg plus pembrolizumab?

At preliminary follow-up, the 750mg combination showed a 57% confirmed overall response rate and 10% complete responses.

How did tumor shrinkage compare between 750mg and 1500mg doses in BCAX data?

Median depth of response was 82% at 1500mg versus 63% at 750mg; 64% of responders at 1500mg had deep responses versus 27% at 750mg.

When will Bicara (BCAX) declare the optimal dose for the FORTIFI-HN01 pivotal study?

The company expects to declare the optimal biologic dose in the first quarter of 2026.

Was the safety profile for BCAX ficerafusp alfa 750mg plus pembrolizumab acceptable?

The 750mg combination was reported as generally well-tolerated, with a safety profile consistent with known ficerafusp alfa plus pembrolizumab data in R/M HNSCC.

Do biomarker data support a specific BCAX dose for deeper responses?

New biomarker data indicate 1500mg achieves greater intratumoral TGF-β inhibition and immune activation, correlating with deeper responses.

How can investors access Bicara’s Dec 6, 2025 webcast about the BCAX data?

An audio webcast was available via the company’s Investor Relations Events and Presentations page, with a replay archived for 30 days.