Preoperative chemotherapy and radiotherapy concomitant to cetuximab in resectable stage IIIB NSCLC: a multicentre phase 2 trial (SAKK 16/08).

BACKGROUND: Neoadjuvant chemotherapy (CT) followed by radiotherapy (RT) and surgery showed a median survival of 28.7 months in resectable stage IIIB non-small-cell lung cancer (NSCLC) patients (pts). Here, we evaluate the impact of concomitant cetuximab to the same neoadjuvant chemo-radiotherapy (CRT) in selected patients (pts) with NSCLC, stage IIIB. METHODS: Resectable stage IIIB NSCLC received three cycles of CT (cisplatin 100 mg/m2 and docetaxel 85 mg/m2 d1, q3w) followed by RT (44 Gy in 22 fractions) with concomitant cetuximab (250 mg/m2, q1w) and subsequent surgery. The primary endpoint was 1-year progression-free survival (PFS). RESULTS: Sixty-nine pts were included in the trial. Fifty-seven (83%) pts underwent surgery, with complete resection (R0) in 42 (74%) and postoperative 30 day mortality of 3.5%. Responses were: 57% after CT-cetuximab and 64% after CRT-cetuximab. One-year PFS was 50%. Median PFS was 12.0 months (95% CI: 9.0-15.6), median OS was 21.3 months, with a 2- and 3-yr survival of 41% and 30%, respectively. CONCLUSIONS: This is one of the largest prospective phase 2 trial to investigate the role of induction CRT and surgery in resectable stage IIIB disease, and the first adding cetuximab to the neoadjuvant strategy. This trial treatment is feasible with promising response and OS rates, supporting an aggressive approach in selected pts.

C reactive protein flare predicts response to checkpoint inhibitor treatment in non-small cell lung cancer.

Biomarkers for predicting response to anti-programmed death-1 (PD-1) immune checkpoint blockade (ICB) in non-small cell lung cancer (NSCLC) remain in demand. Since anti-tumor immune activation is a process, early dynamic changes of the acute-phase reactant C reactive protein (CRP) may serve as a predictive on-treatment biomarker. In a retrospective (N=105) and prospective (N=108) ICB-treated NSCLC cohort, early CRP kinetics were stratified after the start of immunotherapy until weeks 4, 6, and 12 as follows: an early doubling of baseline CRP followed by a drop below baseline (CRP flare-responder), a drop of at least 30% below baseline without prior flare (CRP responders), or those who remained as CRP non-responders. In our study, we observed characteristic longitudinal changes of serum CRP concentration after the initiation of ICB. In the prospective cohort, N=40 patients were defined as CRP non-responders, N=39 as CRP responders, and N=29 as CRP flare-responders with a median progression-free survival (PFS) of 2.4, 8.1, and 14.3 months, respectively, and overall survival (OS) of 6.6, 18.6, and 32.9 months (both log-rank p<0.001). Of note, CRP flare-responses, characterized by a sharp on-treatment CRP increase in the first weeks after therapy initiation, followed by a decrease of CRP serum level below baseline, predict ICB response as early as 4 weeks after therapy initiation. Of note, early CRP kinetics showed no predictive value for chemoimmunotherapy or when steroids were administered concurrently. On-treatment CRP kinetics had a predictive value for both major histological NSCLC subtypes, adenocarcinoma and squamous cell carcinoma. The results were verified in an independent retrospective cohort of 105 patients. In conclusion, CRP flare predicted anti-PD-1 monotherapy response and survival in two independent cohorts including a total of 213 patients with NSCLC, regardless of histology. Due to its wide clinical availability, early CRP kinetics could become an easily determined, cost-efficient, and non-invasive biomarker to predict response to checkpoint inhibitors in NSCLC within the first month.