BridgeBio Oncology (BBOT) Spotlights Next-Gen RAS Pipeline, $425M Cash Runway Into 2028

BridgeBio Oncology Therapeutics (NASDAQ:BBOT) used a presentation at Leerink Partners’ Global Healthcare Conference to outline its strategy around “next-generation RAS therapeutics,” highlighting three clinical-stage small-molecule programs and the company’s focus on achieving a high therapeutic index through both efficacy and tolerability.

Chief Financial Officer Uneek Mehra said the company ended December 2025 with $425 million in cash, which management expects will fund operations into 2028. Mehra also said all three programs are expected to have updates in the second half of 2026, calling it “a very exciting year for us up ahead.”

Portfolio focus: KRAS and a “RAS–PI3K breaker”

Management framed BBOT’s approach as optimized target coverage across two major oncogenic pathways: RAS and PI3K alpha. The company’s three clinical assets include:

• BBO-8520, a direct “on/off” KRAS G12C inhibitor
• BBO-11818, an “on/off” pan-KRAS inhibitor
• BBO-10203, a “RAS–PI3K breaker” designed to block the interaction between RAS and PI3K alpha

In addition to standalone development, Mehra emphasized potential internal combinations across the portfolio, including planned combinations of BBO-10203 with both BBO-11818 and BBO-8520 later in the second half of the year.

BBO-8520: Differentiated mechanism and checkpoint inhibitor combination rationale

Chief Scientific Officer Pedro Beltran described limitations of current “off-only” KRAS G12C inhibitors, arguing they inhibit KRAS only in its GDP-bound “off” state and do not block effector binding when KRAS is in its GTP-bound “on” state. Beltran said BBO-8520 is designed to address this by blocking effector binding in the on state, including to RAF1 and PI3K alpha, which he characterized as a differentiated mechanism that could improve activity.

Mehra pointed to data the company said it published in January, including 65% overall response rate (ORR) in monotherapy, 68% six-month progression-free survival (PFS), and 83% of patients eligible for six-month follow-up remaining on therapy.

Discussion also focused on the longstanding challenge of combining KRAS G12C inhibitors with checkpoint blockade due to liver toxicity observed with other agents. Beltran outlined BBOT’s hypothesis that high circulating levels of covalent drug may contribute to liver toxicity, potentially through mechanisms such as “hapten creation,” particularly when combined with PD-1 inhibitors. He said BBO-8520’s design enables PK/PD “decoupling,” potentially allowing lower free-drug exposure.

Mehra said BBOT identified a 500 mg dose as active and is combining it with pembrolizumab, adding that the company continues to see “very low liver toxicity.” He cited combination experience in 15 patients at 500 mg, with one Grade 3 liver toxicity case that was attributed to a co-medication (an anti-arrhythmic), and described the dataset as “very clean.” Management also noted early signals in a difficult-to-treat subgroup: STK11/KEAP1 co-mutant disease, which they said represents roughly 25%–35% of KRAS G12C non-small cell lung cancer.

Looking ahead, the company said next updates for BBO-8520 will include additional durability data and further pembrolizumab combination safety and efficacy results in the second half.

BBO-11818: Pan-KRAS positioning and early PDAC response

BBOT positioned BBO-11818 as a more narrowly targeted alternative to “pan-RAS” or “multi-RAS” approaches, arguing that expanding beyond KRAS could add safety liabilities without proportionate efficacy benefit. Beltran said the company believes KRAS is the key driver in major carcinomas such as lung, pancreatic, and colorectal cancer, and that avoiding broader RAS inhibition may reduce toxicities associated with wild-type pathway suppression, citing stomatitis and rash as prominent concerns seen elsewhere.

Mehra said BBO-11818 is an oral, reversible on/off inhibitor, and the company disclosed what it characterized as the first announced partial response for a pan-KRAS inhibitor in the field: a pancreatic cancer patient with a reported 56% tumor reduction, announced in January.

On dosing, Mehra said BBOT has shown data up to 600 mg BID, with safety data extending to 800 mg BID, and that the dose escalation remains ongoing. He said the company has not yet observed dose-limiting toxicity, noting two gastrointestinal cases in patients with pre-existing conditions. Additional monotherapy and combination efficacy data are expected in the second half. The company said it is pursuing combinations including chemotherapy in pancreatic cancer, cetuximab in colorectal cancer, and pembrolizumab in non-small cell lung cancer.

BBO-10203: “Breaker” concept aims to avoid PI3K hyperglycemia

Beltran described BBO-10203 as a small molecule that binds PI3K alpha and prevents activation by RAS, characterizing it as distinct from PI3K kinase inhibitors because it does not inhibit kinase activity directly. He said this is intended to avoid insulin receptor signaling disruption and the hyperglycemia commonly associated with PI3K pathway inhibition.

Mehra said BBOT presented roughly 32 patients of safety data and identified 500 mg as a dose for combination work. He said the monotherapy portion was designed to move quickly to combination testing and that the company did not expect meaningful single-agent responses, but reported a 62% disease control rate and tumor reductions without confirmed responses. He emphasized that, despite having no HbA1c restrictions in the trial, the company has observed no hyperglycemia to date.

BBOT is enrolling three combination cohorts: HER2-positive disease with trastuzumab, HR-positive/HER2-negative disease with fulvestrant, and KRAS-mutant disease with chemotherapy. Management said it plans to provide a second-half update including safety and efficacy across all three combinations and expects to treat at full doses with combination partners.

In Q&A, management said mechanisms behind liver toxicity in the broader KRAS inhibitor class remain unproven, with multiple hypotheses discussed and no definitive animal model to validate them. The company reiterated that its working view—lower free-drug exposure leading to improved tolerability—has been consistent with its animal work and early human data.

About BridgeBio Oncology Therapeutics (NASDAQ:BBOT)

BridgeBio Oncology Therapeutics (NASDAQ:BBOT) is a publicly traded biotechnology company focused on discovering and developing therapies for cancer. The company concentrates on translating scientific insights into clinical-stage programs aimed at addressing oncology indications with unmet medical need.

BridgeBio Oncology’s activities center on research and development of investigational therapeutics, advancing drug candidates through preclinical studies and clinical trials. Its work typically involves in-house discovery efforts and collaborations with academic and industry partners to identify targets, optimize compounds, and generate the clinical data needed to support regulatory development.

Public information about BridgeBio Oncology Therapeutics’ specific programs, geographic operations and leadership is limited in the sources available here.