According to the reported data, patients receiving tam-peli achieved a median overall survival (OS) of 13.3 months, compared with 9.4 months for those treated with topotecan. The findings position the investigational ADC among a growing group of B7-H3-directed therapies being developed for relapsed SCLC.

The competitive landscape has become increasingly crowded. Merck & Co. and Daiichi Sankyo have already submitted a B7-H3 ADC for U.S. regulatory review based on phase 2 data demonstrating a median OS of 12 months in second-line disease. More recently, GSK partner Hansoh Pharma reported a median OS of 18.5 months for its B7-H3 ADC in a phase 3 trial involving Chinese patients with relapsed SCLC.

While direct comparisons across separate studies should be interpreted cautiously because of differences in patient populations and trial design, the available results suggest Roche’s candidate falls between the outcomes reported by its major competitors.

Safety remains an important differentiator in the ADC class, particularly regarding interstitial lung disease (ILD), a potentially serious treatment-related toxicity. In MediLink’s phase 3 trial, grade 3 ILD occurred in just 0.9% of patients receiving tam-peli, and no cases of more severe ILD were reported.

Those findings compare favorably with other B7-H3 ADC programs. Reported rates of grade 3 ILD were 3.9% for the GSK-Hansoh candidate and 4.4% for the Merck-Daiichi Sankyo therapy. In the latter program, two treatment-related deaths were attributed to ILD or pneumonitis.

Investigators also highlighted a generally manageable safety profile for tam-peli. Severe treatment-related adverse events of grade 3 or higher occurred in 46.4% of patients receiving the ADC, a lower rate than observed with topotecan. By comparison, Hansoh’s phase 3 study reported grade 3 or worse treatment-related adverse events in 60.9% of participants, while the Merck-Daiichi phase 2 trial reported a rate of 36.5%.

The latest results add to growing momentum for tam-peli. Earlier this year, MediLink announced positive phase 3 findings for the ADC in nasopharyngeal carcinoma. Following the recent successes, Roche has indicated plans to rapidly advance a global phase 3 development program for the therapy.

Roche strengthened its position in the B7-H3 field in January through a licensing agreement granting the company rights to tam-peli outside China. The deal included up to $570 million in near-term payments and expanded Roche’s strategy in SCLC, an area where the company already has a commercial presence. In 2025, the FDA approved a first-line maintenance regimen combining Roche’s Tecentriq with Jazz Pharmaceuticals’ Zepzelca for extensive-stage SCLC, and Roche has identified the indication as an important contributor to Tecentriq’s recent growth.

As multiple B7-H3-targeted therapies move through late-stage development and Amgen’s approved T-cell engager Imdelltra competes in the second-line setting, future commercial success may depend not only on efficacy but also on safety and tolerability advantages. Roche’s latest data suggest tam-peli could emerge as a noteworthy contender in that evolving treatment landscape.