Optimal Duration of Maintenance Checkpoint Inhibitor Therapy in Patients With Advanced NSCLC

Impact of pembrolizumab treatment duration on overall survival and prognostic factors in advanced non-small cell lung cancer: a nationwide retrospective cohort study

Background

The efficacy of front-line pembrolizumab has been established in studies that limit treatment duration to 2 years, but decision to stop pembrolizumab after 2 years is often at physician's discretion. ATHENA is a retrospective cohort study using a comprehensive administrative database aimed firstly at exploring the optimal duration of pembrolizumab and secondly real-life prognosis factors in patients with advanced non-small cell lung cancer (NSCLC).

Methods

Using the French National Health Insurance database (SNDS), we identified patients with incident lung cancer in France from 2015 to 2022. Treatments and patients' characteristics were extracted or inferred from hospital, outpatient care, pharmacy delivery reports. The duration's hazard ratio (HR) was estimated with Cox model weighted by inverse of propensity score to account for confounding. Prognostics factors in first line population were identified with Cox model selected by a LASSO procedure.

Findings

391,106 patients with lung cancer were identified, of whom 43,359 received up-front pembrolizumab for an advanced disease. There were 67% (29,040/43,359) of male and the median age at diagnosis was 65 years old. After a median follow-up time of 25.9 months (min-max, [0-97.6]), the median overall survival (OS) after pembrolizumab initiation in first line was 15.7 [CI 95, 15.3-16.0] months. In multivariable analysis, several covariables were independently associated with worse OS, including male sex with chemo-immunotherapy, age, hospital category, high deprivation index, inpatient hospitalization for first pembrolizumab, and history of diabetes, diuretic, beta blocker, painkiller prescription. At landmark time of 29 months after pembrolizumab initiation, continuation beyond 2 years was not associated with better OS than a fixed 2-year treatment, HR = 0.97 [0.75-1.26] p = 0.95.

Interpretation

This study supports the notion that stopping pembrolizumab after 2 years could be safe for patients with advanced NSCLC. However, because observational studies are prone to confounding and selection bias, causality cannot be affirmed.

Funding

This study did not receive any specific grant.

Circulating Tumor DNA Monitoring on Chemo-immunotherapy for Risk Stratification in Advanced Non-Small Cell Lung Cancer

PURPOSE

Chemoimmunotherapy (chemoIO) is a prevalent first-line treatment for advanced driver-negative non-small cell lung cancer (NSCLC), with maintenance therapy given after induction. However, there is significant clinical variability in the duration, dosing, and timing of maintenance therapy after induction chemoIO. We used circulating tumor DNA (ctDNA) monitoring to inform outcomes in patients with advanced NSCLC receiving chemoIO.

EXPERIMENTAL DESIGN

This retrospective study included 221 patients from a phase III trial of atezolizumab+carboplatin+nab-paclitaxel versus carboplatin+nab-paclitaxel in squamous NSCLC (IMpower131). ctDNA monitoring used the FoundationOne Tracker involving comprehensive genomic profiling of pretreatment tumor tissue, variant selection using an algorithm to exclude nontumor variants, and multiplex PCR of up to 16 variants to detect and quantify ctDNA.

RESULTS

ctDNA was detected (ctDNA+) in 96% of pretreatment samples (median, 93 mean tumor molecules/mL), and similar ctDNA dynamics were noted across treatment arms during chemoIO. ctDNA decrease from baseline to C4D1 was associated with improved outcomes across multiple cutoffs for patients treated with chemoIO. When including patients with missing plasma or ctDNA- at baseline, patients with ctDNA- at C4D1 (clearance), had more favorable progression-free survival (median 8.8 vs. 3.5 months; HR, 0.32;0.20-0.52) and OS (median not reached vs. 8.9 months; HR, 0.22; 0.12-0.39) from C4D1 than ctDNA+ patients.

CONCLUSIONS

ctDNA monitoring during induction chemoIO can inform treatment outcomes in patients with advanced NSCLC. Importantly, monitoring remains feasible and informative for patients missing baseline ctDNA. ctDNA testing during induction chemoIO identifies patients at higher risk for disease progression and may inform patient selection for novel personalized maintenance or second-line treatment strategies.

Immunotherapy and Hypofractionated Radiotherapy in Older Patients with Locally Advanced Cutaneous Squamous-Cell Carcinoma of the Head and Neck: A Proposed Paradigm by the International Geriatric Radiotherapy Group

Cutaneous skin carcinoma is a disease of older patients. The prevalence of cutaneous squamous-cell carcinoma (cSCC) increases with age. The head and neck region is a frequent place of occurrence due to exposure to ultraviolet light. Surgical resection with adjuvant radiotherapy is frequently advocated for locally advanced disease to decrease the risk of loco-regional recurrence. However, older cancer patients may not be candidates for surgery due to frailty and/or increased risk of complications. Radiotherapy is usually advocated for unresectable patients. Compared to basal-cell carcinoma, locally advanced cSCC tends to recur locally and/or can metastasize, especially in patients with high-risk features such as poorly differentiated histology and perineural invasion. Thus, a new algorithm needs to be developed for older patients with locally advanced head and neck cutaneous squamous-cell carcinoma to improve their survival and conserve their quality of life. Recently, immunotherapy with checkpoint inhibitors (CPIs) has attracted much attention due to the high prevalence of program death ligand 1 (PD-L1) in cSCC. A high response rate was observed following CPI administration with acceptable toxicity. Those with residual disease may be treated with hypofractionated radiotherapy to minimize the risk of recurrence, as radiotherapy may enhance the effect of immunotherapy. We propose a protocol combining CPIs and hypofractionated radiotherapy for older patients with locally advanced cutaneous head and neck cancer who are not candidates for surgery. Prospective studies should be performed to verify this hypothesis.

Anti-PD-1 immunotherapy with dose-adjusted ultra-hypofractionated re-irradiation in patients with locoregionally recurrent head and neck cancer

INTRODUCTION

Patients with recurrent inoperable squamous-cell head-neck cancer (HNSCC) after chemo-radiotherapy have an ominous prognosis. Re-irradiation can be applied with some efficacy and high toxicity rates. Anti-PD-1 immunotherapy is effective in 25% of patients. Immunogenic death produced by large radiotherapy (RT) fractions may enhance immune response.

MATERIALS AND METHODS

We evaluated the efficacy and tolerance of ultra-hypofractionated immuno-radiotherapy (uhypo-IRT) in 17 patients with recurrent HNSCC and 1 with melanoma. Four of HNSCC patients also had oligometastatic disease. Using a dose/time/toxicity-based algorithm, 7, 7 and 4 patients received 1, 2 and 3 fractions of 8 Gy to the tumor, respectively. Nivolumab anti-PD-1 immunotherapy was administered concurrently with RT and continued for 24 cycles, or until disease progression or manifestation of immune-related adverse events (irAEs).

RESULTS

Early and late RT toxicities were minimal. Three patients developed irAEs (16%). After the 12th cycle, 7/17 (41.2%) and 5/17 (29.4%) patients with HNSCC showed complete (CR) and partial response (PR), respectively. CR was also achieved in the melanoma patient. The objective response rates in HNSCC patients were 57%, 86% and 66%, after 1, 2 and 3 fractions, respectively (overall response rate 70.6%). Most responders experienced an increase in peripheral lymphocyte counts. The median time to progression was 10 months. The 3-year projected locoregional progression-free survival was 35%, while the 3-year disease-specific overall survival was 50%.

CONCLUSIONS

Anti-PD1 uhypo-IRT is safe and effective in patients with recurrent HNSCC. The high objective response rates and the long survival without evidence of disease support further trials on uhypo-IRT.

A systematic review and meta-analysis on the Optimal Treatment duration of cHEckpoint inhibitoRS in solid tumors: the OTHERS study

No clear evidence supports the advantage of fixed (up to two years (2yICI)) or continuous treatment (more than two years (prolonged ICI)) in cancer patients achieving stable disease or response on immune checkpoint inhibitors (ICIs). We performed a systematic review and meta-analysis of randomized controlled trials reporting the duration of ICIs (alone or in combination with standard of care (SoC)) across various solid tumors. Overall, we identified 28,417 records through database searching. Based on the eligibility criteria, 57 studies were identified for the quantitative synthesis, including 22,977 patients receiving ICIs (with or without SoC). Prolonged ICI correlated with better overall survival (OS) than 2yICI in patients with melanoma (HR:1.55; 95%CI: 1.22,1.98), while 2yICI-SoC led to better OS than prolonged ICI-SoC in patients with NSCLC (HR: 0.84; 95%CI: 0.68,0.89). Prospective randomized trials are needed to assess the most appropriate duration of ICIs. OBJECTIVE: No clear evidence supports the advantage of fixed (up to two years (2yICI)) or continuous treatment (more than two years (prolonged ICI)) in cancer patients achieving stable disease or response on immune checkpoint inhibitors (ICIs). Here, we assessed the optimal treatment duration for ICIs in solid tumors. CONCLUSIONS: Prolonged ICIs administration does not seem to improve the outcomes of patients with NSCLC an RCC.

Is anti-PD-1 immunotherapy a means for post-irradiation tumor clearance in head and neck cancer?

Chemo-radiotherapy is the standard treatment for locally advanced head-neck cancer (LA-HNC). However, about 30% of tumors do not respond or even progress shortly after the completion of radiotherapy. We investigated whether anti-PD1 immunotherapy can eradicate the irradiated tumor and reverse the ominous prognosis of these patients. We retrospectively analyzed a small series of 9 patients with LA-HNC who did not respond (6/9) or showed local disease progression (3/9) during chemo-radiotherapy and were treated with nivolumab anti-PD1 immunotherapy. Immunotherapy started 1.5 months after the end of radiotherapy. Out of 9 patients, 3 (33.3%) had a complete response and 3 (33.3%) partial response at 6 months after the onset of immunotherapy. Two patients are alive with no evidence of disease at 36 months. One more patient with partial response and without disease progression survived 16 months after therapy when he died from intercurrent disease. Immunotherapy showed an excellent tolerance profile. One patient developed an extensive skin rash on the 16th cycle. Anti-PD-1 immunotherapy after radiotherapy can lead to clearance of the remnant tumor and ameliorate the prognosis of patients. Randomized trials are necessary to establish post-irradiation immunotherapy as a standard of care in this ill-fated subgroup of HNC patients.