Zai Lab (ZLAB) Investor update summary

First-line efficacy and durability

• At the September 2026 data cut-off, zoci 1.6 mg/kg plus atezolizumab achieved an 81.8% confirmed ORR (27/33; 95% CI 64.5–93.0) in 1L ES-SCLC; ORR across dose levels was 81.4%.

• Six-month PFS was 81.9% in the 1.6 mg/kg doublet cohort; median PFS was not reached among the first 15 patients after median follow-up of 10 months, with 10/15 progression- and death-free at cutoff.

• Responses were rapid, with 34/35 responders responding by the first post-baseline assessment; median duration of response was not reached in the first 15 patients after 10 months’ median follow-up.

• Across 13 patients and dose levels, the atezolizumab-carboplatin triplet achieved a 92.3% ORR, 8.4-month median PFS and 7.7-month median duration of response.

Safety and tolerability

• In the 1.6 mg/kg doublet cohort, zoci-related Grade ≥3 AEs occurred in 9.1% (3/33); no treatment-related discontinuations or deaths were reported, and one Grade 1 ILD/pneumonitis case occurred.

• Across doublet dose levels, ZL-1310-related Grade ≥3 AEs occurred in 16.3% and related SAEs in 11.6%; dose reduction was 4.7%, discontinuation 2.3%, and no treatment-related deaths were reported.

• Triplet Grade ≥3 TEAEs were 76.9% across doses versus 21.2% with the 1.6 mg/kg doublet; triplet treatment had more hematologic toxicity and dose interruptions, including one treatment-related death after carboplatin overdose and Grade 5 sepsis.

Development strategy and milestones

• A global randomized Phase 3 study of zoci plus an IO regimen in 1L ES-SCLC is expected to start by year-end 2026; the planned trial may allow lurbi as maintenance.

• The Phase 3 DLLEVATE study in previously treated ES-SCLC is ongoing; the potentially registrational extrapulmonary NEC study is fully enrolled, with a potential BLA submission next year.

• Zoci is being developed as a potential chemotherapy-sparing frontline ADC backbone with IO and potentially a T-cell engager, aiming to reduce attrition between induction and maintenance.

• Global early studies are evaluating zoci with tarlatamab in ES-SCLC and obrixtamig in NEC; TCE combinations are also being explored with Amgen and Boehringer Ingelheim.

• Other development opportunities include limited-stage SCLC, large cell neuroendocrine carcinoma and DLL3-expressing brain tumors; second-line brain-metastasis analysis showed activity in over 60% of patients.