Gemcitabine plus erlotinib followed by capecitabine versus capecitabine plus erlotinib followed by gemcitabine in advanced pancreatic cancer: final results of a randomised phase 3 trial of the 'Arbeitsgemeinschaft Internistische Onkologie' (AIO-PK0104)

Abstract

Objective: AIO-PK0104 investigated two treatment strategies in advanced pancreatic cancer (PC): a reference sequence of gemcitabine/erlotinib followed by 2nd-line capecitabine was compared with a reverse experimental sequence of capecitabine/erlotinib followed by gemcitabine.

Methods: 281 patients with PC were randomly assigned to 1st-line treatment with either gemcitabine plus erlotinib or capecitabine plus erlotinib. In case of treatment failure (eg, disease progression or toxicity), patients were allocated to 2nd-line treatment with the comparator cytostatic drug without erlotinib. The primary study endpoint was time to treatment failure (TTF) after 1st- and 2nd-line therapy (TTF2; non-inferiority design). KRAS exon 2 mutations were analysed in archival tumour tissue from 173 of the randomised patients.

Results: Of the 274 eligible patients, 43 had locally advanced and 231 had metastatic disease; 140 (51%) received 2nd-line chemotherapy. Median TTF2 was estimated with 4.2 months in both arms; median overall survival was 6.2 months with gemcitabine/erlotinib followed by capecitabine and 6.9 months with capecitabine/erlotinib followed by gemcitabine, respectively (HR 1.02, p=0.90). TTF for 1st-line therapy (TTF1) was significantly prolonged with gemcitabine/erlotinib compared to capecitabine/erlotinib (3.2 vs 2.2 months; HR 0.69, p=0.0034). Skin rash was associated with both TTF2 (rash grade 0/1/2-4:2.9/4.3/6.7 months, p<0.0001) and survival (3.4/7.0/9.6 months, p<0.0001). Each arm showed a safe and manageable toxicity profile during 1st- and 2nd-line therapy. A KRAS wild-type status (52/173 patients, 30%) was associated with an improved overall survival (HR 1.68, p=0.005).

Conclusion: Both treatment strategies are feasible and demonstrated comparable efficacy; KRAS may serve as biomarker in patients with advanced PC treated with erlotinib.

Trial registration: ClinicalTrials.gov NCT00440167.

Figure 1

CONSORT diagram, Cap, Capecitabine; E, Erlotinib; Gem, Gemcitabine; Pts, Patients.

Figure 2

Time-to-treatment failure (TTF) and overall survival (OS). (A) TTF2, (B) TTF1, (C) OS. Exploratory analysis on overall survival (OSc) after start of 2nd-line chemotherapy (‘cross-over patient population’, n=140). (D) OSc.

Figure 3

Time-to-treatment failure 2 (TTF2, A) and overall survival (OS, B) grouped by intensity of skin rash (grade 0‒4, according to NCI-CTCv2.0).