Background: Sequential treatment of Panitumumab (Pb) plus Paclitaxel (Px) as induction treatment (IT) followed by concurrent bioradiotherapy (Bio-RT) with Pb may be an alternative for locally advanced squamous cell carcinoma of the head and neck (LA-SCCHN) in patients ineligible for high-dose cisplatin therapy.
Methods: Phase II, single-arm, multicentre study, with two-stage design, in patients ≥ 18 years with stage III-IVa-b LA-SCCHN unfit for platinum. Patients received Px + Pb (9 weeks) as IT followed by Bio-RT + Pb. Primary endpoint: overall response rate (ORR) after IT, defined as: more than 70% of patients achieving complete response (CR) or partial response (PR) to IT. Secondary end-points: progression-free survival, organ preservation rate, safety profile.
Results: Study ended prematurely (51 patients) due to slow recruitment. ORR: 66.7% (95% CI: 53.7-79.6), 8 (15.7%) CR and 26 (51.0%) PR. 39 patients (76%) completed radiotherapy (RT). Pb and/or Px-related adverse events (AEs) grade 3-4: 56.9% during IT and 63.4% during the concomitant phase, of which most common were skin toxicity (33.3%). Five deaths occurred during treatment, two of them (3.9%) were Pb and/or Px-related.
Conclusions: Although underpowered, ORR was higher than the pre-specified boundary for considering the treatment active. Although Px + Pb as IT provides some benefit, the safety profile is worse than expected. To consider Pb + Px as IT as an alternative for platinum-unsuitable LA-SCCHN, further research/investigation would be needed.
Keywords: Comorbidity; EGFR tyrosine kinase inhibitor; Head and neck neoplasms; Induction chemotherapy; Panitumumab; Squamous cell carcinoma.