SNTI shares rip higher on positive clinical data, oversubscribed PIPE deal

Senti Biosciences, Inc. (SNTI) reported promising initial data from its Phase 1 clinical trial of SENTI-202, a novel CAR-NK investigational cell therapy for relapsed/refractory (R/R) hematologic malignancies, particularly acute myeloid leukemia (AML). The therapy is designed to target CD33 and FLT3-expressing malignancies while sparing healthy bone marrow cells. This off-the-shelf therapy represents a potential breakthrough in a space with limited options for patients whose disease has progressed beyond first-line or venetoclax-based treatments. The early results from the trial suggest that SENTI-202 could address this unmet need effectively.

Among the three AML patients treated at the initial dose level of 1.0 billion CAR+ NK cells per dose, two achieved complete remission (CR) confirmed by bone marrow biopsy. These patients also became measurable residual disease (MRD) negative, indicating no detectable cancer cells in their bone marrow by the most sensitive methods available. Both patients have maintained remission for over three and four months, respectively. Importantly, SENTI-202 was well-tolerated, with an adverse event profile consistent with standard lymphodepleting chemotherapy, underscoring its favorable safety profile even at this early stage.

Dr. Kanya Rajangam, Senti Bio's Chief Medical Officer, highlighted the significance of these early results, particularly the rapid and deep responses observed at the lowest dose level. These findings, coupled with a manageable safety profile, provide encouraging signals for the therapy’s potential efficacy. The company is optimistic about generating further data in 2025 as it continues dose-escalation studies to determine optimal dosing and evaluate the durability of the responses.

Senti Bio plans to enroll approximately 20 patients in the ongoing trial, with a higher-dose cohort of 1.5 billion CAR+ NK cells per dose already underway. The company aims to release additional safety, efficacy, and durability data next year. The early success of SENTI-202 positions it as a potential game-changer for treating AML, a disease that remains highly challenging with few effective options for patients with relapsed or refractory cases. These results mark an important milestone for Senti Biosciences as it advances its Gene Circuit platform in cell and gene therapy development.

SNTI announced a $37.6 million private investment in public equity (PIPE) financing involving the issuance of Series A Convertible Preferred Stock to existing and new accredited investors. This transaction, anticipated to close by December 5, 2024, includes warrants allowing investors to purchase up to an additional 25 million common shares upon stockholder approval. Additionally, an option for one investor to purchase further preferred stock could bring in an extra $10 million by December 27, 2024. Leading the financing round are notable investors such as Celadon Partners, New Enterprise Associates (NEA), and Leaps by Bayer, with Leerink Partners serving as the placement agent.

The PIPE financing is significant for Senti Bio as it provides critical funding to advance its SENTI-202 program, particularly in manufacturing scale-up and ongoing clinical development. SENTI-202, a cutting-edge CAR-NK cell therapy for treating relapsed/refractory hematologic malignancies, has shown promising early results in Phase 1 trials. This infusion of capital will also support broader research and development initiatives and general corporate purposes, helping Senti Bio sustain its momentum as a clinical-stage biotech innovator.

This PIPE financing reflects strong investor confidence in Senti Bio's Gene Circuit platform and its potential to deliver transformative therapies in areas with high unmet medical needs, such as acute myeloid leukemia (AML). The involvement of high-profile institutional investors not only underscores the strategic importance of the company’s pipeline but also enhances its credibility and ability to attract further funding. Additionally, the structure of the financing, including convertible preferred stock and warrants, aligns investor interests with the company's long-term success.

The transaction is essential for ensuring Senti Bio has the resources to continue its ambitious R&D agenda, especially as it advances its lead program and scales manufacturing capabilities. The agreement’s registration rights provision ensures future flexibility in offering the securities publicly, facilitating broader participation from the investment community while adhering to regulatory standards. This PIPE financing strengthens Senti Bio's position as it seeks to transform cell and gene therapy through its proprietary platform and innovative product pipeline.