Safety And Efficacy Of Atezolizumab (Atezo) In Patients (Pts) With Autoimmune Disease (Aid): Subgroup Analysis Of The Tail Study.

e21628 Background: Atezo showed improved survival and a manageable safety profile in advanced NSCLC. The Phase III/IV TAIL study (NCT03285763) evaluated atezo in pts with previously treated advanced NSCLC, including pts often excluded from pivotal trials. We analyzed outcomes in pts with a history of AID in TAIL. Methods: Pts had stage IIIb/IV NSCLC that progressed after 1-2 lines of chemo and ECOG PS ≤ 2. Eligible pts included those with preexisting AID. Pts received atezo 1200 mg IV q3w. The primary endpoint was safety as measured by the incidence of treatment-related (TR) serious AEs (SAEs) and TR immune-related AEs (irAEs). Secondary endpoints included OS, PFS, ORR and other safety measures. Results: Of the 619 pts enrolled, 615 received atezo, including 30 pts with AID. In AID pts, the median age was 67 y, 43.3% were male and 86.7% had ECOG PS 0-1; common preexisting conditions included psoriasis (n = 7) and rheumatoid arthritis (n = 5). 23 pts had active AID at baseline. At data cutoff (Jun 4 2019), median follow-up was 12.7 mo. TR SAEs occurred in 6.7% and 7.9% of AID vs non-AID pts, respectively; TR irAEs occurred in 10.0% and 8.2% (table). AEs occurring in AID pts at a ≥ 10% difference vs non-AID pts were decreased appetite (26.7%), nausea (26.7%), dyspnea (23.3%) and pneumonitis (13.3%). G3-4 AE incidences were similar between groups (30.0% vs 29.9%). AEs leading to treatment discontinuation occurred in 16.7% and 4.3% of AID vs non-AID pts and included G1-2 pneumonitis (6.7%), G3-4 pleural infection (3.3%) and G3-4 pneumonia (3.3%). AEs of special interest (AESI) occurred more frequently in AID (40.0%) vs non-AID (34.2%) pts, with pneumonitis (13.3% vs 3.1%), rash (13.3% vs 10.6%) and hypothyroidism (6.7% vs 9.6%) as the most common AESIs in either group. Exploratory efficacy analyses in AID vs non-AID pts showed an mOS of 10.1 vs 11.1 mo, an mPFS of 2.9 vs 2.7 mo and ORRs of 10.0% vs 11.1%. Conclusions: Despite the small number of AID pts, safety and efficacy outcomes of atezo in TAIL pts with a history of AID were similar to those of pts with no history of AID. Moderate AE increases seen in AID pts tended to be respiratory in nature or GI disorders. These data may inform treatment decisions in pts with advanced NSCLC and AID. Clinical trial information: NCT03285763. [Table: see text]