Phase II study of RAD001 (everolimus) and depot octreotide (sandostatin LAR) in advanced low grade neuroendocrine carcinoma (LGNET)

Abstract

4503 Background: Effective systemic therapy for advanced LGNET is lacking. Mutations involving the mTOR pathway including TSC2, NF-1, and vHL are associated with development of LGNET. mTOR also mediate signaling downstream of IGF1 and VEGF. RAD001 is a novel oral mTOR inhibitor. Octreotide has been described to inhibit VEGF and IGF1 production in solid tumors. Methods: Patients (pts) received depot octreotide 30 mg q28 days, and RAD001 5 (pts 1–30) or 10 mg (pts 31–60) po daily. Response was evaluated every 12 weeks (wks). Results: 30 carcinoid (C) and 30 islet cell (I) patients (pts) were enrolled between 2/05–7/06. 38 pts (23 C, 15 I) had prior octreotide. By RECIST criteria, there were 10 PR (17%), 45 SD (75%) (15 pts had > 15% reduction), 5 PD (8%). The response rates within C, and I groups were 13% and 20%. The response rates within the 5 mg and 10 mg groups were 13% and 20% respectively. Of 39 pts with PD prior to study entry, there were 7 (18%) PR, 27 (69%) SD (9 pts had > 15% reduction), 5 (13%) PD. PFS rate at 24 wks was 86%. The median PFS duration is 59 wks. The median PFS duration among the C and I groups were 69 and 39 wks. Among the 39 pts with progression at study entry, the median PFS duration was 38 wks. Of 24 pts with elevated chromogranin A at entry, 19 (56%) had > 50% reduction. Treatment was well tolerated. The most common toxicity was mild aphthous ulceration. CTC G3/4 toxicities included: thrombocytopenia (3), neutropenia (3), hypophosphatemia (5), hyperglycemia (4), hypoglycemia (2), hypokalemia (2), fatigue (6), diarrhea (6), aphthous ulcer (5), rash (3), and 1 each of anemia, hypertriglyceridemia, bilirubin, AST/ALT, pain, nausea, nail, dysgeusia, pneumonitis. Conclusions: RAD001 at 5 or 10 mg daily was well tolerated in combination with octreotide. Promising anti-tumor activity has been observed. The RADIANT (RAD001 In Advanced Neuroendocrine Tumors) trials are underway to evaluate RAD001 in larger patient groups. No significant financial relationships to disclose.