Safety profile of avelumab in patients with advanced solid tumors: A JAVELIN pooled analysis of phase 1 and 2 data.

3059 Background: Avelumab is a fully human IgG1 anti–PD-L1 antibody with clinical activity in several tumor types. Pooled safety data from a large phase 1 trial in various tumors and a phase 2 trial in Merkel cell carcinoma (NCT01772004, NCT02155647) were analyzed to further characterize the safety profile of avelumab. Methods: Patients (pts) received avelumab 10 mg/kg 1-hour IV Q2W until progression, unacceptable toxicity, or withdrawal. Treatment-related adverse events (TRAEs) were graded by NCI CTCAE. In post hoc analyses, immune-related adverse events (irAEs) were identified via an expanded AE list and medical review, and infusion-related reaction (IRR) events were identified based on prespecified MedDRA terms, occurring within 1 day or related symptoms that resolved within 2 days of infusion. Results: In 1,738 pts analyzed (phase 1, n = 1,650; phase 2, n = 88) who received ≥1 dose of avelumab for a median of 12 weeks (range 2-138), the most common any grade TRAEs were fatigue (n = 307, 18%), IRR (n = 295, 17%), and nausea (n = 150, 9%). 177 pts (10%) had a grade ≥3 TRAE; most common were fatigue and elevated lipase (17 [1%] each). TRAEs led to discontinuation in 107 pts (6%). Four pts (0.2%) died due to a TRAE. Any grade irAEs occurred in 247 pts (14%), which were grade ≥3 in 39 pts (2%) and considered serious in 43 pts (2%). The most common any grade irAEs were thyroid disorder (n = 98, 6%) and rash (n = 90, 5%). Other irAEs (eg, colitis, hepatitis, pneumonitis, adrenal insufficiency, myositis) each occurred in < 2%. irAEs led to discontinuation in 34 pts (2%). IRR or related symptoms (eg, chills, pyrexia, hypersensitivity) occurred in 439 pts (25%), which were grade 3 in 9 pts (0.5%) and grade 4 in 3 pts (0.2%). An IRR occurred at first infusion in 79% and within first 4 doses in 99%; 63/439 pts (14%) had IRR recurrence in later cycles. IRR led to dose interruption in 152 (9%), infusion rate reduction in 124 (7%), and discontinuation in 35 pts (2%). Conclusions: This large pooled analysis confirms that avelumab has an acceptable safety profile. A minority of pts experienced a grade ≥3 TRAE or irAE and discontinuation due to TRAEs was uncommon. IRRs mostly occurred at first infusion and the rate of recurrence was low. Clinical trial information: NCT01772004, NCT02155647.