Korro Bio Reports $1.5 Million Collaboration Revenue and Increased Operating Losses in Q2 2025

Korro Bio, Inc. reported its financial results for the second quarter of 2025, revealing a collaboration revenue of $1.5 million for the three months ended June 30, 2025, and $4.0 million for the six-month period, marking a significant increase from no revenue in the same periods of 2024. The company’s total operating expenses rose to $28.7 million for the quarter and $56.2 million for the half-year, compared to $24.1 million and $45.6 million, respectively, in the prior year. The net loss for the second quarter was $25.8 million, compared to a loss of $21.8 million in the same quarter of 2024, while the loss for the first half of 2025 was $49.2 million, up from $41.4 million in 2024.

The increase in operating expenses was primarily driven by higher research and development costs, which totaled $21.0 million for the second quarter, up from $17.1 million in the prior year. This rise was attributed to increased spending on the development of the KRRO-110 program for Alpha-1 Antitrypsin Deficiency (AATD) and other pre-development activities. General and administrative expenses also increased, reflecting higher personnel-related costs, including stock-based compensation and severance related to a workforce reduction initiated in May 2025, which saw a 19% reduction in staff.

Korro Bio's operational developments included the ongoing Phase 1/2a REWRITE clinical trial for KRRO-110, with dosing of participants initiated in January 2025. The company has expanded its clinical trial into New Zealand and is progressing towards additional geographic expansion. As of June 30, 2025, the company had cash, cash equivalents, and marketable securities totaling $119.6 million, which it expects will fund operations into 2027. However, the company continues to face significant risks, including the need for substantial additional funding to support its research and development efforts.

Looking ahead, Korro Bio anticipates continued operating losses as it advances its clinical programs and seeks regulatory approvals. The company has not yet commercialized any product candidates and does not expect to generate revenue from product sales in the near term. The management has indicated that future capital requirements will depend on various factors, including the progress of clinical trials and the potential for collaboration agreements. The company remains focused on its strategic objectives, including the development of its RNA editing technology and the expansion of its product pipeline.