3170 - A First-in-Human Phase 1/2 Trial of the Oral HIF-2a Inhibitor PT2977 in Patients with Advanced RCC

Background

Hypoxia-inducible factor (HIF)-2α is a transcription factor that is a key oncogenic driver in renal cell carcinoma (RCC). PT2977 is a potent and selective small molecule HIF-2α inhibitor that prevents HIF-2α from heterodimerizing with HIF-1β, blocking the expression of HIF-2α target genes in tumour cells, and inducing regressions in mouse xenograft RCC models.

Methods

Patients with advanced solid tumours were treated with PT2977 in a dose-escalation design to determine the recommended Phase 2 dose (RP2D). Patients with advanced clear cell RCC who had received at least one prior therapy were enrolled in an expansion cohort at the RP2D of 120 mg orally once daily.

Results

55 pts were treated with PT2977 120 mg (three in dose escalation; 52 in expansion). Median number of prior therapies was 3 (1-9). 73% of patients were intermediate risk and 18% were poor risk by IMDC criteria. As of March 15, 2019, the most common all-grade, all-cause adverse events (AEs) > 25% are anemia (75%), fatigue (64%), dyspnea (44%), nausea (33%), peripheral edema (29%) and cough (27%). Anemia (20%) and hypoxia (11%) are the most common Grade 3 AEs and on-target effects of HIF2α inhibition. Discontinuation due to a treatment-related AE was reported in 2 patients (4%). 13 patients (24%) experienced a confirmed PR and 30 patients (54%) had SD, with a clinical benefit rate of 78%. Follow-up for all patients has been at least 40 weeks and the probability of PFS at 40 weeks is 50.1%.

Conclusions

PT2977 is well tolerated and has a favorable safety profile. The clinical activity of PT2977 shows promise for the treatment of RCC. A PT2977 monotherapy Phase 3 trial in previously treated advanced RCC patients is planned.

Clinical trial identification

NCT02974738.

Editorial acknowledgement

Legal entity responsible for the study

Peloton Therapeutics, Inc.

Funding

Peloton Therapeutics, Inc.

Disclosure

E. Jonasch: Advisory / Consultancy, Research grant / Funding (self): Exelixis; Research grant / Funding (institution): Peloton Therapeutics; Advisory / Consultancy, Research grant / Funding (institution): Novartis; Advisory / Consultancy, Research grant / Funding (institution): Pfizer; Advisory / Consultancy: Eisai; Advisory / Consultancy: Genentech; Advisory / Consultancy: Ipsen. E.R. Plimack: Research grant / Funding (institution): Peloton Therapeutics; Research grant / Funding (institution): Astellas; Advisory / Consultancy, Research grant / Funding (institution): Bristol-Myers Squibb; Advisory / Consultancy, Research grant / Funding (institution): Genentech; Advisory / Consultancy, Research grant / Funding (institution): Merck; Advisory / Consultancy, Research grant / Funding (institution): Pfizer; Advisory / Consultancy: Incyte; Advisory / Consultancy: Janssen; Advisory / Consultancy: AstraZeneca. T. Bauer: Research grant / Funding (institution): Peloton Therapeutics; Research grant / Funding (institution): ARMO Biosciences; Research grant / Funding (institution): Foundation Medicine; Research grant / Funding (institution): Phosplatin Therapeutics; Research grant / Funding (institution): Karyopharm Therapeutics; Research grant / Funding (institution): Takeda; Research grant / Funding (institution): Janssen; Advisory / Consultancy, Research grant / Funding (institution): Loxo; Research grant / Funding (institution): Top Alliance BioScience; Research grant / Funding (institution): Five Prime Therapeutics; Research grant / Funding (institution): Astellas Pharma; Research grant / Funding (institution): Sanofi; Advisory / Consultancy, Research grant / Funding (institution): Moderna Therapeutics; Research grant / Funding (institution): Bristol-Myers Squibb; Advisory / Consultancy: Pfizer; Research grant / Funding (institution): Aileron Therapeutics; Research grant / Funding (institution): Roche; Research grant / Funding (institution): Calithera Biosciences; Advisory / Consultancy, Research grant / Funding (institution): Ignyta; Research grant / Funding (institution): Immugen. J.R. Merchan: Research grant / Funding (institution): Peloton Therapeutics; Advisory / Consultancy: Exelixis; Research grant / Funding (institution): Genentech; Research grant / Funding (institution): Seattle Genetics; Research grant / Funding (institution): Astellas; Research grant / Funding (institution): Tocagen; Research grant / Funding (institution): Vyriad; Research grant / Funding (institution): Silagen; Research grant / Funding (institution): Novartis; Research grant / Funding (institution): Eli Lilly; Research grant / Funding (institution): Eisai; Research grant / Funding (institution): Corvus; Research grant / Funding (institution): RepImmune; Research grant / Funding (institution): Rexahn. K.P. Papadopoulos: Research grant / Funding (institution): Peloton Therapeutics; Research grant / Funding (institution): AbbVie; Research grant / Funding (institution): Amgen; Research grant / Funding (institution): ADC Therapeutics; Research grant / Funding (institution): ARMO Biosciences; Advisory / Consultancy, Research grant / Funding (institution): ArQule; Advisory / Consultancy, Research grant / Funding (institution): Bayer; Research grant / Funding (institution): Calithera Biosciences; Research grant / Funding (institution): Daiichi Sankyo; Research grant / Funding (institution): 3D Medicines; Research grant / Funding (institution): EMD Serono; Research grant / Funding (institution): Syros Pharmaceuticals; Research grant / Funding (institution): Incyte; Research grant / Funding (institution): Jounce Therapeutics; Research grant / Funding (institution): MabSpace Biosciences; Research grant / Funding (institution): MedImmune; Research grant / Funding (institution): Merck; Research grant / Funding (institution): Mersana; Research grant / Funding (institution): Regereron; Research grant / Funding (institution): Sanofi. D.F. McDermott: Advisory / Consultancy, Research grant / Funding (institution): Peloton Therapeutics; Honoraria (self), Advisory / Consultancy: Bristol-Myers Squibb; Honoraria (self), Advisory / Consultancy: Pfizer; Honoraria (self), Advisory / Consultancy: Merck; Honoraria (self), Advisory / Consultancy: Novartis; Honoraria (self), Advisory / Consultancy: Eisai; Honoraria (self), Advisory / Consultancy: Exelixis; Honoraria (self), Advisory / Consultancy: Array BioPharm; Honoraria (self), Advisory / Consultancy: Genentech; Honoraria (self), Advisory / Consultancy: Eli Lilly; Honoraria (self), Advisory / Consultancy: EMD Serono; Research grant / Funding (institution): Prometheus Laboratories; Research grant / Funding (institution): Bristol-Myers Squibb; Honoraria (self): Jounce Therapeutics. M.D. Michaelson: Research grant / Funding (institution): Peloton Therapeutics; Advisory / Consultancy, Research grant / Funding (institution): Eisai; Research grant / Funding (institution): Novartis; Advisory / Consultancy, Research grant / Funding (institution): Pfizer; Research grant / Funding (institution): Merck; Advisory / Consultancy: Exelixis. L.J. Appleman: Research grant / Funding (institution): Peloton Therapeutics; Research grant / Funding (institution): Pfizer; Research grant / Funding (institution): Novartis; Research grant / Funding (institution): Exelixis; Research grant / Funding (institution): Bristol-Myers Squibb; Research grant / Funding (institution): Astellas; Research grant / Funding (institution): Acerta; Research grant / Funding (institution): Bayer; Research grant / Funding (institution): Agensys; Research grant / Funding (institution): Merck; Research grant / Funding (institution): Genentech; Research grant / Funding (institution): Tokai; Research grant / Funding (institution): AVEO; Research grant / Funding (institution): Calithera; Research grant / Funding (institution): Seattle Genetics; Research grant / Funding (institution): Inovio; Research grant / Funding (institution): Eisai; Research grant / Funding (institution): Eli Lilly. S. Thamake: Shareholder / Stockholder / Stock options, Full / Part-time employment: Peloton Therapeutics. N. Zojwalla: Shareholder / Stockholder / Stock options, Full / Part-time employment: Peloton Therapeutics. T.K. Choueiri: Honoraria (self), Advisory / Consultancy, Research grant / Funding (self), Research grant / Funding (institution): Peloton Therapeutics; Advisory / Consultancy, Research grant / Funding (self), Research grant / Funding (institution): Tracon; Honoraria (self), Advisory / Consultancy, Research grant / Funding (self), Research grant / Funding (institution): AstraZeneca; Honoraria (self), Advisory / Consultancy, Research grant / Funding (self), Research grant / Funding (institution): Bayer; Honoraria (self), Advisory / Consultancy, Research grant / Funding (self), Research grant / Funding (institution): Bristol-Myers Squibb; Honoraria (self), Advisory / Consultancy, Research grant / Funding (self), Research grant / Funding (institution): Eisai; Honoraria (self), Advisory / Consultancy, Research grant / Funding (self), Research grant / Funding (institution): Foundation Medicine; Honoraria (self), Advisory / Consultancy, Research grant / Funding (self), Research grant / Funding (institution): Exelixis; Honoraria (self), Advisory / Consultancy, Research grant / Funding (self), Research grant / Funding (institution): Ipsen; Honoraria (self), Advisory / Consultancy, Research grant / Funding (self), Research grant / Funding (institution): Genentech; Honoraria (self), Advisory / Consultancy, Research grant / Funding (self), Research grant / Funding (institution): Roche; Honoraria (self), Advisory / Consultancy, Research grant / Funding (self), Research grant / Funding (institution): GlaxoSmithKline; Honoraria (self), Advisory / Consultancy, Research grant / Funding (self), Research grant / Funding (institution): Merck; Honoraria (self), Advisory / Consultancy, Research grant / Funding (self), Research grant / Funding (institution): Novartis; Honoraria (self), Advisory / Consultancy, Research grant / Funding (self), Research grant / Funding (institution): Pfizer; Honoraria (self), Advisory / Consultancy, Research grant / Funding (self), Research grant / Funding (institution): Prometheus Labs; Research grant / Funding (self), Research grant / Funding (institution): Calithera; Advisory / Consultancy, Research grant / Funding (self), Research grant / Funding (institution): Analysis Group; Research grant / Funding (self), Research grant / Funding (institution): Takeda; Honoraria (self), Advisory / Consultancy: Alexion.