Oligo-residual disease in PD-1/PD-L1 inhibitor-treated metastatic non-small cell lung cancer: incidence, pattern of failure, and clinical value of local consolidative therapy.

OBJECTIVES: To investigate the feasibility and potential clinical value of local consolidative therapy (LCT) in PD-1/PD-L1 inhibitor-treated metastatic non-small cell lung cancer (NSCLC). MATERIALS AND METHODS: PD-1/PD-L1 inhibitor-treated metastatic NSCLC patients with measurable disease in three academic centers were screened and those with adequate follow-up were included. Oligo-residual disease (ORD) was defined as residual tumors limited to three organs and five lesions evaluated at the best response among patients with partial response or stable disease after PD-1/PD-L1 inhibitors. Oligometastatic and multiple-metastatic disease (OMD/MMD) were similarly classified at baseline. Locoregional interventions, administered after effective treatment of PD-1/PD-L1 inhibitors and before initial disease progression, were defined as LCT. Patterns of initial progressive disease (PD) were classified as involving only residual sites (RP), only new sites (NP), or a combination of both (BP). RESULTS: Among the 698 patients included, ORD was documented in 73 (47.1%) of 155 patients with baseline OMD and 60 (11.0%) of 543 patients with baseline MMD. With a median follow-up of 31.0 (range, 6.0-53.0) months, 108 patients with ORD developed initial PD, with RP, NP, and BP occurring in 51 (47%), 23 (21.3%), and 34 (31.5%), respectively. Among the 133 patients with ORD, those receiving LCT (n = 43) had longer progression-free survival (HR = 0.58, 95% CI 0.40-0.85, p = 0.01) and overall survival (HR = 0.49, 95% CI 0.30-0.79, p < 0.0001). CONCLUSION: ORD occurs with a clinically relevant frequency among PD-1/PD-L1 inhibitor-treated metastatic NSCLC patients and LCT may provide extra survival benefits in those with ORD.

Pamiparib as consolidation treatment after concurrent chemoradiotherapy of limited-stage small cell lung cancer: a single-arm, open-label phase 2 trial.

BACKGROUND: Small cell lung cancer (SCLC) is highly invasive with poor prognosis, and its treatment has historically been hindered due to the absence of targetable driver genomic alterations. However, the high genomic instability and replication stress in SCLC have made poly(ADP-ribose) polymerases (PARPs) inhibitors a focus of research. Pamiparib is an orally available PARP1/2 inhibitor with high selectivity, strong PARP trapping activity, and excellent brain penetration. Utilizing pamiparib as consolidation maintenance therapy in limited-stage SCLC holds promise for improving survival outcomes and offering a viable therapeutic approach. METHODS: This single-arm, open-label phase II trial will enroll patients aged 18-75 years with histologically/cytologically confirmed, limited-stage SCLC who have not progressed following definitive platinum-based cCRT and have an ECOG PS of 0 or 1. Patients will be excluded if they have histologically confirmed mixed SCLC or NSCLC, or have undergone previous tumor resection, or can be treated with surgery or stereotactic body radiation therapy/stereotactic ablative radiation therapy. Participants will receive pamiparib 40 mg twice daily every 3 weeks within 2 to 6 weeks after cCRT for up to 1 year or until disease progression according to RECIST v1.1. The primary endpoint is the 1-year progression-free survival (PFS) rate assessed by investigators per RECIST v1.1. Secondary endpoints include PFS, objective response rate, and duration of response assessed by investigators per RECIST 1.1, overall survival, time to distant metastasis, and safety. DISCUSSION: The study will provide valuable data on the feasibility, safety, and effectiveness of pamiparib as a consolidation therapy after cCRT in patients with LS-SCLC. The correlation between molecular typing or gene expression profile of the disease and curative response will be further explored. TRIAL REGISTRATION: NCT05483543 at clinicaltrials.gov.