BBOT Reports Second Quarter 2026 Financial Results and Update on Corporate Progress

• Continued to advance monotherapy and combination cohorts for all clinical programs
• Initiated dosing of BBO-11818 in combination with cetuximab and after the end of the quarter, initiated dosing of BBO-11818 in combination with BBO-10203
• Presented preclinical data at AACR highlighting the potency and activity of BBO-11818 in KRAS mutant tumor models and the efficacy of BBO-10203 in combination with tucatinib and trastuzumab in HER2amp models
• Cash runway expected to fund operations into 2028

SOUTH SAN FRANCISCO, Calif., Aug. 11, 2026 — BridgeBio Oncology Therapeutics, Inc. (“BBOT”) (Nasdaq: BBOT), a clinical-stage biopharmaceutical company focused on RAS-pathway malignancies, today reported financial results for the second quarter ended June 30, 2026, and provided a business update.

BBOT’s portfolio of RAS-pathway inhibitors is designed to enable direct dual inhibition of KRASG12C (BBO-8520), or KRASG12D/V (BBO-11818) in both its ON and OFF states as well as disruption of RAS-driven PI3Kα activation (BBO-10203) to achieve optimal target coverage of the most mutated driver oncogene in human cancer. Together, these assets uniquely position BBOT to achieve concurrent, high-level suppression of both the MAPK and PI3Kα pathways through a wholly-owned internal combination strategy.

“During the second quarter, we made meaningful progress in patient enrollment in our monotherapy and combination cohorts across each of our three clinical programs. Differentiated patient benefit in oncology is driven by optimal target coverage and the ability to combine with standard-of-care regimens. Therefore, we continue to focus heavily on advancing our combination development strategies,” said Pedro J. Beltran, Ph.D., Chief Executive Officer of BBOT. “In addition, our wholly-owned portfolio is uniquely positioned to enable concurrent suppression of the MAPK and PI3Kα pathways through internal combination strategies of each of our KRAS inhibitors with BBO-10203. We are excited to have both combinations already underway in patients. With multiple near-term clinical milestones across all programs expected in the second half of 2026 and cash runway into 2028, we believe we are well positioned to execute our strategy and expand treatment options for patients with mutant KRAS-driven cancers.”

Key Program Highlights and Updates

BBO-8520: An orally bioavailable small molecule direct inhibitor targeting both the ON and OFF states of KRAS**G12C.**

• Continued to enroll BBO-8520 plus pembrolizumab combination in patients with NSCLC carrying KRASG12C mutation.
• Initiated BBO-8520 plus BBO-10203 combination in patients with G12C NSCLC.

BBO-11818: An orally bioavailable small molecule pan-KRAS inhibitor that targets mutant KRAS in both the ON and OFF states.

• Continued to enroll BBO-11818 monotherapy across multiple dose levels.
• Initiated dosing of BBO-11818 in combination with cetuximab.
• Subsequent to the end of the quarter, initiated dosing of BBO-11818 in combination with BBO-10203.
• Presented preclinical data at AACR highlighting the potency of BBO-11818 in KRASG12D and KRASG12V CDX models, potent combination effect with cetuximab or BBO-10203, and complete tumor regressions through adaptive immunity in combination with anti PD-1 antibodies.

BBO-10203: An orally bioavailable small molecule with a novel mechanism of action designed to block the physical interaction between RAS and PI3Kα, inhibiting RAS-driven PI3Kα-AKT signaling in tumors.

• Continued to enroll HR+ BC, HER2+/HR- BC, and colorectal (CRC) combination cohorts.
• Presented preclinical data at AACR showing that BBO-10203 demonstrated strong in vivo combination effect with HER2 inhibitors tucatinib or trastuzumab in HER2amp tumor models.

Second Quarter 2026 Financial Results

• Cash Position: As of June 30, 2026, BBOT had cash, cash equivalents and marketable securities totaling $344.1 million, which is expected to provide cash runway into 2028.
• Research and development (R&D) expenses: R&D expenses were $49.2 million for the second quarter of 2026 compared to $27.4 million for the second quarter of 2025. The increase in expenses was primarily due to increases in clinical trial expenses and manufacturing expenses for BBO-8520, BBO-11818, and BBO-10203.
• General and administrative (G&A) expenses: G&A expenses were $11.0 million for the second quarter of 2026 compared to $2.7 million for the second quarter of 2025. The increase in G&A expenses reflects the initiation of BBOT's standalone operations, de-SPAC transaction, and one-time severance costs for former executives.
• Net Loss: Net loss was $56.5 million for the second quarter of 2026 compared to $28.4 million for the second quarter of 2025.

About BBOT

BBOT is a clinical-stage biopharmaceutical company advancing a next-generation pipeline of novel small molecule therapeutics targeting RAS and PI3Kα malignancies. BBOT has the goal of improving outcomes for patients with cancers driven by the two most prevalent oncogenes in human tumors. For more information, please visit http://www.bbotx.com and follow us on LinkedIn.

Investor Contact

BBOT [email protected]

Media Contact

Inizio Evoke Comms [email protected]

BridgeBio Oncology Therapeutics, Inc. Condensed Consolidated Statements of Operations (in thousands, except shares and per share amounts)

Three Months Ended June 30,

Six Months Ended June 30,

2026

2025

2026

2025

Operating expenses:

(unaudited)

(unaudited)

Research and development

$

49,225

$

27,438

$

89,027

$

48,073

General and administrative

10,962

2,655

17,339

5,157

Total operating expenses

60,187

30,093

106,366

53,230

Loss from operations

(60,187

)

(30,093

)

(106,366

)

(53,230

)

Other income, net:

Interest income

3,551

1,666

7,495

3,475

Interest from transition services agreements

196

—

419

—

Change in fair value of participation right liability

—

—

—

(725

)

Other income (expense)

(14

)

(8

)

(108

)

(10

)

Total other income, net

3,733

1,658

7,806

2,740

Net loss

$

(56,454

)

$

(28,435

)

$

(98,560

)

$

(50,490

)

Net loss per share attributable to common stockholders, basic and diluted

$

(705.20

)

$

(566.46

)

$

(1,230.89

)

$

(1,168.26

)

Weighted-average number of shares used in computing net loss per share attributable to common stockholders, basic and diluted

80,054

50,198

80,072

43,218

Selected Condensed Consolidated Balance Sheet Data (in thousands)

June 30,

December 31,

2026

2025

(unaudited)

Cash and cash equivalents and marketable securities

$

344,130

$

425,460

Total assets

376,706

448,381

Total liabilities

53,594

37,285

Accumulated deficit

(455,127

)

(356,567

)

Total stockholders’ equity

323,112

411,096