Phase II study of the oral hypoxia-inducible factor 2α (HIF-2α) inhibitor MK-6482 for Von Hippel-Lindau (VHL) disease-associated clear cell renal cell carcinoma (ccRCC).

Authors

null

Othon Iliopoulos

Massachusetts General Hospital Cancer Center and Harvard Medical School, Boston, MA

Othon Iliopoulos , Eric Jonasch , Frede Donskov , Vivek Narayan , Benjamin Louis Maughan , Stephane Oudard , Tobias Else , Jodi K. Maranchie , Sarah J. Welsh , Sanjay Thamake , Rodolfo F. Perini , Eric Kristopher Park , W. Marston Linehan , Ramaprasad Srinivasan , W. Kimryn Rathmell

Organizations

Massachusetts General Hospital Cancer Center and Harvard Medical School, Boston, MA, The University of Texas MD Anderson Cancer Center, Houston, TX, Aarhus University Hospital, Aarhus, Denmark, University of Pennsylvania, Philadelphia, PA, University of Utah, Salt Lake City, UT, Hôpital Européen Georges-Pompidou, Paris, France, University of Michigan, Ann Arbor, MI, University of Pittsburgh, Pittsburgh, PA, Cambridge University Hospitals NHS Foundation Trust, Cambridge, United Kingdom, Merck & Co., Inc., Kenilworth, NJ, National Cancer Institute, Bethesda, MD, Center for Cancer Research, National Cancer Institute, Bethesda, MD, Vanderbilt University, Nashville, TN

Research Funding

Pharmaceutical/Biotech Company
Merck Sharp & Dohme Corp., a subsidiary of Merck & Co., Inc., Kenilworth, NJ, USA.

Background: Patients (pts) with VHL disease are at risk of developing benign and malignant tumors, including ccRCC, pancreatic lesions tumors, CNS hemangioblastomas, and retinal lesions. Inactivation of VHL leads to stabilization of HIF-2α, which drives tumor growth. In a phase 1/2 study, MK-6482, a potent, selective, oral small molecule HIF-2α inhibitor, demonstrated favorable safety and antitumor activity in advanced ccRCC. We present results of the open-label phase 2 study of MK-6482 for VHL disease–associated ccRCC (NCT03401788). Methods: Adults with germline VHL alterations, measurable, localized/non-metastatic ccRCC, no prior systemic anticancer therapy, and ECOG PS 0/1 received MK-6482 120 mg once daily until progression, intolerable toxicity, or decision to withdraw. Primary end point: ORR of VHL-associated ccRCC tumors per RECIST v1.1 by independent review committee (IRC). Secondary end points: DOR, time to response (TTR), PFS, and safety. Results: As of June 1, 2020, 61 pts enrolled. The majority (82%) of pts had ECOG PS 0, and median number of prior surgeries per pt was 5 (range, 1-15). Lesions outside the kidney (non-RCC tumors) evaluable by IRC included pancreatic lesions (100%) and CNS hemangioblastomas (70%). Median duration of treatment was 68 wk (range, 8-105), and 92% of pts remain on therapy. There were 22 confirmed responses (ORR, 36% [95% CI, 24%-49%]) and 7 (11%) unconfirmed (documented at 1 time point, to be confirmed at subsequent time point) responses; all PRs. In pts with confirmed PR, median DOR was not reached (range, 12-62 wk) and median TTR was 31 wk (range, 12-61); 14 (64%) pts had response duration of ≥26 wk. 56 pts (92%) had any decrease in size of target lesions. PFS rate at 52 wk was 98% (95% CI, 89%-100%). Overall, pretreatment median linear growth rate of ccRCC tumors was +3.6 mm/y (range, −3.4 to +33.1), compared with −4.5 mm/y (range, −12.8 to +5.1) while on treatment. For non-RCC tumors, ORR in pancreatic lesions was 64% (39/61, including 4 CRs) and in CNS hemangioblastomas was 30% (13/43, including 5 CRs). Median (range) TTR was 35 wk (11-60) and 12 wk (10-60) for pancreatic lesions and CNS hemangioblastomas, respectively. 11/16 (69%) pts with evaluable retinal lesions at baseline showed improvement. Of those 16 pts, 29 eyes were followed for retinal lesions; 16 eyes (55%) showed improvement, 12 (41%) remained stable, and no follow-up evaluation was available for 1 (3%) eye. Treatment-related AEs (TRAEs) occurred in 98% of pts, none grade 4/5. Most common TRAE was anemia (87%), considered to be an on-target toxicity. One pt discontinued treatment due to a TRAE (grade 1 dizziness). As of data cutoff, 1 pt (2%) required surgery for ccRCC tumors after treatment. Conclusions: MK-6482 is an active and well-tolerated therapy for VHL disease–associated ccRCC, pancreatic lesions, as well as CNS and retinal hemangioblastomas. Clinical trial information: NCT03401788.

Disclaimer

This material on this page is ©2024 American Society of Clinical Oncology, all rights reserved. Licensing available upon request. For more information, please contact licensing@asco.org

Abstract Details

Meeting

2021 Genitourinary Cancers Symposium

Session Type

Poster Session

Session Title

Poster Session: Renal Cell Cancer

Track

Renal Cell Cancer

Sub Track

Therapeutics

Clinical Trial Registration Number

NCT03401788

Citation

J Clin Oncol 39, 2021 (suppl 6; abstr 333)

DOI

10.1200/JCO.2021.39.6_suppl.333

Abstract #

333

Poster Bd #

Online Only

Abstract Disclosures