SN BioScience has initiated the first patient dosing in its global phase 1b/2 clinical trial evaluating SNB-101, a nanoparticle anticancer agent, in patients with Extensive-Stage Small Cell Lung Cancer (ES-SCLC).

This multi-center trial, conducted across sites globally including the US and Europe, will enroll up to 135 patients. The study is designed in 3 sequential stages: a phase 1b dose-escalation phase using a 3+3 design to determine the Maximum Tolerated Dose (MTD) at dose levels of 50–70 mg/m², followed by a two-part phase 2 consisting of phase 2a and phase 2b. Phase 2a will conduct dose optimisation to identify the optimal therapeutic dose, after which phase 2b will proceed with dose expansion at the optimised dose to further evaluate clinical activity across a broader patient population. Across phase 2, key efficacy endpoints including Objective Response Rate (ORR), Progression-Free Survival (PFS), and Overall Survival (OS) will be assessed to generate the clinical evidence necessary to support regulatory review process.

The advancement into phase 2 is supported by encouraging prior phase 1 results conducted in Korea, in which SNB-101 demonstrated a favorable safety profile with no Grade 3 or higher diarrhea events, a Disease Control Rate (DCR) of 83.3 percent in high-dose cohorts, and a mean PFS of 6.3 months in SCLC patients. These findings compare favorably with outcomes historically reported for currently available later-line treatment options, including Zepzelca and Topotecan.

Based on its phase 1 results, SNB-101 was granted Fast Track Designation by the US Food and Drug Administration (FDA) for SCLC. Together with Orphan Drug Designation from the FDA and EMA, these designations reflect that SNB-101 has fully established the regulatory framework necessary to pursue accelerated approval.

As a monotherapy, SNB-101 has demonstrated encouraging clinical activity together with a favorable tolerability profile in previously treated SCLC patients. The company believes these findings support the continued clinical development of SNB-101 as a potential treatment option for patients with relapsed SCLC, particularly in later-line settings where tolerability and efficacy remain an important unmet need.

In parallel with the ongoing monotherapy program, SN BioScience is actively expanding the development of SNB-101 into combination strategies with immunotherapy agents (including anti-PD-1, anti-PD-L1, and DLL3-targeted BiTE T-cell engager therapies) currently used in standard SCLC treatment. The company has already obtained EMA approval for a clinical study evaluating SNB-101 in combination with one immunotherapy agent, and is planning to submit an additional CTA within this year for a separate study involving another immunotherapy combination.

In addition, SN BioScience is pursuing the expansion of SNB-101 into additional solid tumor indications, including gastric and pancreatic cancers, through ongoing collaborations and strategic discussions with global pharmaceutical companies.