POSITIVE RESULTS

Kelun-Biotech's sac-TMT plus Keytruda hits PFS goal in PD-L1-negative NSCLC

OptiTROP-Lung06's interim analysis is the first Phase 3 ADC-immunotherapy combination to clear its primary endpoint in driver-negative, PD-L1-negative NSCLC, a segment where checkpoint inhibitors alone underperform.

By AppliedXLJuly 14, 2026Trial NCT06711900

Executive Summary

Kelun-Biotech's antibody-drug conjugate paired with pembrolizumab produced a statistically significant progression-free survival benefit over chemotherapy plus pembrolizumab in a first-line lung cancer population that responds poorly to immunotherapy alone.
The trial targets patients whose tumors lack PD-L1 expression and any targetable driver mutation, a population underserved by the current immunotherapy-chemotherapy standard, and the result marks the second consecutive Phase 3 success for this drug combination.
The finding builds on an earlier positive Phase 3 result for the same combination in a PD-L1-positive population, positioning the pairing as a broader first-line NSCLC regimen rather than a single-trial result.
The company intends to bring the results to China's national drug regulator, and the trial continues toward its confirmatory analysis and overall survival maturation.

The readout

Kelun-Biotech disclosed on July 14, 2026 that the OptiTROP-Lung06 trial met its primary endpoint of progression-free survival, assessed by blinded independent central review, at a prespecified interim analysis. The randomized, open-label Phase 3 study, registered as NCT06711900, enrolled 432 patients with locally advanced or metastatic non-squamous NSCLC whose tumors carry a PD-L1 tumor proportion score below 1% and test negative for EGFR, ALK, ROS1, NTRK, and BRAF V600E alterations. Patients received sacituzumab tirumotecan (sac-TMT, also known as SKB264/MK-2870) plus pembrolizumab, compared against pembrolizumab combined with pemetrexed and platinum-based chemotherapy, the first-line standard for this population. The company said the combination produced a statistically significant and clinically meaningful improvement in PFS, along with a positive trend in overall survival, and that safety was consistent with prior sac-TMT data with no new safety signals. Kelun-Biotech+1

Probability of Success

Endpoint Met96%

Completes88%

Clinical Significance73%

Regulatory90%

What the endpoint tests

PD-L1-negative non-squamous NSCLC is the segment of lung cancer least likely to respond to PD-1 blockade alone, since low PD-L1 expression correlates with weaker checkpoint-inhibitor activity. The trial's design pairs an antibody-drug conjugate that targets Trop2, a cell-surface protein expressed on NSCLC tumor cells, with pembrolizumab's PD-1 blockade, testing whether ADC-driven cell killing can prime an immune response the checkpoint inhibitor alone cannot generate in low-PD-L1 tumors. Kelun-Biotech's own framing describes the strategy as intended to unlock pembrolizumab's activity in patients with limited immune responsiveness, though that mechanistic rationale is the hypothesis the trial's mature data will need to bear out, not an established finding. Kelun-Biotech

Reading the interim result

The disclosed result comes from a prespecified interim analysis rather than the trial's final data cut, and the underlying red flag attached to the readout notes the data remain immature. The trial's primary completion date is registered as December 1, 2026, and enrollment has held flat at its 432-patient target with no eligibility or endpoint amendments recorded since the study opened in October 2024, indicating a stable and on-track protocol rather than one under operational strain. The company said it plans to communicate the results to the Center for Drug Evaluation of China's National Medical Products Administration. NCT06711900+1

Where it fits

This is the second Phase 3 trial of sac-TMT plus pembrolizumab to report a positive primary-endpoint result, following the earlier OptiTROP-Lung05 study in PD-L1-positive first-line NSCLC, whose findings were presented at the 2026 ASCO meeting and published in The Lancet. Among antibody-drug conjugates being tested in NSCLC, sac-TMT itself is also in Phase 3 development in a different Merck-sponsored trial pairing it with pembrolizumab in the resectable, PD-L1-agnostic setting, while other Trop2, HER2, MET, and CDH6-directed ADCs from Daiichi Sankyo, AbbVie, and AstraZeneca are advancing through Phase 2 and 3 NSCLC programs using varied combination partners. The distinguishing feature of OptiTROP-Lung06 is its focus on the PD-L1-negative, driver-negative subgroup, a population that most of those competing ADC and checkpoint-inhibitor combinations have not targeted as a primary registration population. Kelun-Biotech

This analysis was produced using AI-assisted reporting systems, AppliedXL data, and official public records. These systems undergo editorial review, quality checks, and regular audits by human experts. Errors may still occur, as with any automated system. Always consult the linked primary sources. Read our AI Editorial Policy.