Preliminary analysis of a phase II, multicenter, randomized, active-control study to evaluate the efficacy and safety of eganelisib (IPI 549) in combination with nivolumab compared to nivolumab monotherapy in patients with advanced urothelial carcinoma

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Background: Inhibition of the PD-1 pathway has demonstrated clinical benefit in metastatic urothelial carcinoma (mUC); however, response rates of 15% to 29% highlight the need for more effective therapies, especially for PD-L1- patients. Eganelisib is a first-in-class, novel, oral agent which selectively inhibits PI3K-γ, with the goal of improving the immune response to checkpoint inhibitors (CPI). Methods: Eligible patients (pts) with mUC who progressed on > 1 platinum-based chemotherapy regimen and were CPI naïve were enrolled. Pts were randomized 2:1 to receive eganelisib in combination with nivolumab (EN) or placebo with nivolumab (PN). Pts were stratified by baseline circulating monocytic myeloid derived suppressor cells (mMDSC) level. The primary endpoint was objective response rate (ORR) per RECIST v1.1 in pts with high baseline mMDSC levels. Other endpoints included ORR, progression free survival (PFS) and overall survival (OS) in all pts and PD-L1 +/- pts. Results: We report preliminary data (as of 9/1/2020) for the first 49 pts with 33 randomized to receive EN and 16 PN. Preliminary ORR/PFS is presented in the table below. Except for the mMDSC high subgroup, ORR and PFS were improved in the EN arm compared to the PN arm. The duration of exposure was a median of 15 weeks for EN and 11 for PN. Most common all-Gr AEs (EN vs PN %) were pyrexia (33 vs 0), decreased appetite (30 vs 19), pruritis (24 vs 6), rash (24 vs 6), asthenia (21 vs 31), and transaminase elevation (21 vs 6). Most common Gr≥3 AEs (EN vs PN %) include hepatotoxicity (15 vs 0), transaminase elevation (12 vs 6), and rash (9 vs 0). Following an early safety review, eganelisib dose was reduced from 40 to 30 mg, resulting in a reduction of hepatic AEs. Conclusions: Preliminary data demonstrates that the combination of eganelisib, once reduced to 30 mg, and nivolumab was well tolerated with hepatic and skin-related toxicities more common in the EN arm. When compared to PN, the combination demonstrated an improved ORR and PFS, especially in the PD-L1- subset. Updated efficacy, including PFS and OS, safety and translational data will be presented. Clinical trial information: NCT03980041 . [Table: see text]

Outcome of men with HIV-associated germ cell cancer: Results from an international collaborative study

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Background: Previous studies showed that men with HIV-associated germ cell cancer (HIV-GCC) have a similar cancer-free outcome compared with their HIV-negative counterparts. However, the overall survival (OS) was inferior and little data is available on treatment and outcome of HIV-GCC in the era of combined antiretroviral therapy (cART). Methods: Men living with HIV aged ≥ 18 years (yrs) with a diagnosis of histologically proven GCC made from 01/1996 to 07/2018 were included. Primary outcomes were OS and progression-free survival (PFS). Secondary outcomes included characteristics of GCC and HIV-infection, treatment and causes of death. Results: Data of 89 men from 23 institutions and 6 countries with a total of 92 HIV-GCC (2 synchronous and 1 metachronous bilateral GCC) were analysed, among them 64 (70%) seminomas and 28 (30%) nonseminomas. 10/89 (11%) cases were primary extragonadal GCC. Median age was 36 yrs (range, 22-52) and median time from HIV to GCC diagnosis was 5 yrs (range, 0-29). Median CD4 count at GCC diagnosis was 420 cells/µl (range, 3-1503) and 83% of pts were on cART. Stage I disease was found in 44/80 (55%) gonadal GCC (metachronous bilateral case included). Of 46 cases with stage II/III/extragonadal GCC 78%, 17% and 4% were assigned to the IGCCCG good, intermediate and poor prognosis group, respectively. Of the 44 stage I cases, 22 (50%) were followed by active surveillance, and 11 (25%) received adjuvant chemotherapy (CT) or radiotherapy. Relapses occurred in 14 pts (6 from stage I, 8 in pts primary disseminated GCC) and CT was applied to 13/14 pts, of which 3 received high-dose CT. Overall, 12/89 (13%) pts have died. Causes of death were refractory GCC (n = 5), an AIDS-defining illness (n = 3) and other (n = 4). After a median follow-up of 6.5 yrs (range, 0.3-20.9), the 5- and 10-year PFS rate was 81% and 73%, and the 5- and 10-year OS rate was 91% and 85%, respectively. There were no significant differences between the good and intermediate prognosis group or between pts with CD4 counts < 200/µl or ≥ 200/µl. Conclusions: The 5- and 10-year PFS and OS rates of men with HIV-GCC are similar to those reported for HIV-negative GCC. Pts with HIV-GCC should remain on cART and be managed in an identical fashion to HIV-negative pts.

DUTRENEO Trial: A randomized phase II trial of DUrvalumab and TREmelimumab versus chemotherapy as a NEOadjuvant approach to muscle-invasive urothelial bladder cancer (MIBC) patients (pts) prospectively selected by an interferon (INF)-gamma immune signature

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Background: Cisplatin-based neoadjuvant chemotherapy (CT) followed by radical cystectomy (RC) is a standard treatment for MIBC. PD-1/L1 inhibitors as single agent induce pathological complete responses (pCR) in this setting. Predictors of response are still ill defined. DUTRENEO trial aimed to prospectively explore the activity of anti-PDL1 + anti-CTLA4 vs CT in pts selected according to a tumor pro-inflammatory IFN-gamma signature (tumor immune score, TIS). Methods: Cisplatin-eligible pts with urothelial MIBC (cT2-T4a, N≤1, M0) candidates to RC were classified as “hot” or “cold” according to a tumor TIS determined by Nanostring technology. Patients with "hot" tumors were randomized to DU 1500 mg + TRE 75 mg every 4 weeks x 3 cycles or standard cisplatin-based CT (GEMCIS or MVACdd). Pts in the “cold” arm received standard CT. Primary endpoint was to achieve ≥8 pCR in the DU+TRE arm. PDL1 expression was assessed using immunohistochemistry. Results: 61 pts were recruited in 10 sites between oct-2018 and dec-2019. Pts randomized in the “hot” arms received standard CT (n = 22) or DU+TRE (n = 23) and had a pCR rate of 8/22 pts (36.4%) vs 8/23 pts (34.8%), respectively [OR = 0.923 (0.26 – 3.24)]. In the “cold” arm, 16 pts received CT obtaining a pCR rate of 68.8% (11/16 pts). There were more PDL1 low tumors in the "cold" TIS arm (10/12, 83.3%). pCR rate by PDL1 status is shown in the table. One pt in the DU+TRE arm refused RC. Full treatment was delivered to 81.3% of CT "cold" vs 59.1% of CT "hot" vs 73.9% in the DU+TRE arm pts. Grade 3-4 toxicities were more frequent in the CT arms. Conclusions: The combination of DU+TRE is safe and active in MIBC patients in the neoadjuvant setting. Nevertheless prospective stratification by a pro-inflammatory IFN-gamma signature failed to select patients more likely to benefit from IO vs CT in this context. Further studies are required to guide treatment selection. Clinical trial information: NCT03472274 . [Table: see text]