Gemcitabine-erlotinib versus gemcitabine-erlotinib-capecitabine in the first-line treatment of patients with metastatic pancreatic cancer: Efficacy and safety results of a phase IIb randomised study from the Spanish TTD Collaborative Group

BACKGROUND

Gemcitabine and erlotinib have shown a survival benefit in the first-line setting in metastatic pancreatic cancer (mPC). The aim of this study was to assess whether combining capecitabine (C) with gemcitabine + erlotinib (GE) was safe and effective versus GE in patients with mPC.

PATIENTS AND METHODS

Previously untreated mPC patients were randomised to receive G (1000 mg/m², days 1, 8, 15) + E (100 mg/day, days 1-28) + C (1660 mg/m², days 1-21) or GE, q4 weeks, until progression or unacceptable toxicity. Primary end-point: progression-free survival (PFS); secondary end-points: overall survival (OS), response rate, relationship of rash with PFS/OS and safety.

RESULTS

120 patients were randomised, median age 63 years, ECOG status 0/1/2 33%/58%/8%; median follow-up 16.5 months. Median PFS in the gemcitabine-erlotinib-capecitabine (GEC) and GE arms was 4.3 and 3.8 months, respectively (hazard ratio [HR]: 0.88, 95% confidence interval [CI]: 0.58-1.31; p = 0.52). Median OS in the GEC and GE arms was 6.8 and 7.7 months, respectively (HR: 1.09, 95% CI: 0.72-1.63; p = 0.69). Grade 3/4 neutropenia (GEC 43% versus GE 15%; p = 0.0008) and mucositis (GEC 9% versus GE 0%; p = 0.03) were the only statistically significant differences in grade 3/4 adverse events. PFS and OS were significantly longer in patients with rash (grade ≥1) versus no rash (grade = 0): PFS 5.5 versus 2.0 months (HR = 0.39, 95% CI: 0.26-0.6; p < 0.0001) and OS: 9.5 versus 4.0 months (HR = 0.51, 95% CI: 0.33-0.77; p = 0.0014).

CONCLUSION

PFS with GEC was not significantly different to that with GE in patients with mPC. Skin rash strongly predicted erlotinib efficacy. The study was registered with ClinicalTrials.gov: NCT01303029.

Dose escalation to rash for erlotinib plus gemcitabine for metastatic pancreatic cancer: the phase II RACHEL study

Background:

This phase II, open-label, randomised study evaluated whether patients with metastatic pancreatic cancer receiving erlotinib/gemcitabine derived survival benefits from increasing the erlotinib dose.

Methods:

After a 4-week run-in period (gemcitabine 1000 mg m⁻² once weekly plus erlotinib 100 mg per day), patients with metastatic pancreatic cancer who developed grade 0/1 rash were randomised to receive gemcitabine plus erlotinib dose escalation (150 mg, increasing by 50 mg every 2 weeks (maximum 250 mg); n=71) or gemcitabine plus standard-dose erlotinib (100 mg per day; n=75). The primary end point was to determine whether overall survival (OS) was improved by increasing the erlotinib dose. Secondary end points included progression-free survival (PFS), incidence of grade ⩾2 rash, and safety.

Results:

Erlotinib dose escalation induced grade ⩾2 rash in 29 out of 71 (41.4%) patients compared with 7 out of 75 (9.3%) patients on standard dose. Efficacy was not significantly different in the dose-escalation arm compared with the standard-dose arm (OS: median 7.0 vs 8.4 months, respectively, hazard ratio (HR), 1.26, 95% confidence interval (CI): 0.88–1.80; P=0.2026; PFS: median 3.5 vs 4.5 months, respectively, HR, 1.09, 95% CI: 0.77–1.54; P=0.6298). Incidence of adverse events was comparable between randomised arms.

Conclusion:

The erlotinib dose-escalation strategy induced rash in some patients; there was no evidence that the higher dose translated into increased benefit.

Systemic treatment of advanced pancreatic cancer

Pancreatic cancer belongs to the most malignant gastrointestinal cancers and, in its advanced stage, remains a deadly disease for nearly all affected patients. Treatment of metastatic adenocarcinoma of the pancreas not only involves chemotherapy and targeted therapy, but also requires attention to accompanying comorbidities as well as frequently intensive supportive treatment and psychosocial support. Gemcitabine-based combinations with fluoropyrimidines and platin analogs have essentially failed to provide a substantial prolongation of survival and may constitute a treatment option only in patients with a good performance status. Among targeted therapies, only the EGFR tyrosine kinase inhibitor erlotinib has shown activity which is marginal in the overall population, but clinically relevant in patients developing skin rash. New avenues of polychemotherapy are presently explored since the gemcitabine-free FOLFIRINOX-regimen (infusional 5-fluorouracil/folinic acid plus irinotecan and oxaliplatin) was shown to be markedly superior to gemcitabine in selected good-performance patients. Pancreatic cancer is notably characterized as a hypovascular tumor rich in desmoplastic stromal tissue. An innovative approach to treatment therefore focuses on peritumoral fibroblasts and aims to induce a depletion of the stroma either by inhibition of the hedgehog pathway or by targeting SPARC (secreted protein acidic and rich in cysteine) via application of albumin-bound paclitaxel.

Phase II open-label study of erlotinib in combination with gemcitabine in unresectable and/or metastatic adenocarcinoma of the pancreas: relationship between skin rash and survival (Pantar study)

BACKGROUND

Skin rash is an adverse event which might be associated with longer survival in patients treated with epidermal growth factor receptor tyrosine kinase inhibitors. The aim of this nonrandomised phase II clinical trial is to prospectively evaluate the relationship between skin rash and overall survival (OS) in advanced/metastatic pancreatic cancer treated with erlotinib plus gemcitabine.

PATIENTS AND METHODS

Patients were given gemcitabine (1000 mg/m2/week, 3 weeks every 4 weeks) plus erlotinib (100 mg/day orally continuously) until disease progression/unacceptable toxicity. The primary end point was OS.

RESULTS

A total of 153 eligible patients were enrolled (grade≥2 rash, 25%; grade<2 rash, 75%). OS was longer in patients with grade≥2 rash versus grade<2 (11 versus 5 months; P<0.001). Progression-free survival was longer in patients with grade≥2 rash versus grade<2 (6 versus 3 months; P<0.001) and shorter in those without rash versus grade 1 (2 versus 4 months; P=0.005) or grade≥2 (2 versus 6 months; P<0.001). Patients with grade≥2 rash showed higher rates of overall response (21% versus 7%; P<0.05) and disease control (84% versus 43%; P<0.05) versus grade<2.

CONCLUSIONS

This study prospectively confirms the relationship between rash and longer OS in unresectable locally advanced/metastatic pancreatic cancer treated with erlotinib plus gemcitabine.