A window-of-opportunity trial reveals mechanisms of response and resistance to navtemadlin in patients with recurrent glioblastoma

Veronica Rendo1,2,3,4,5*†, Eudocia Q. Lee1,3,6*†, Connor Bossi7, Nicholas Khuu1,2,4,

Michelle A. Rudek8‡, Sangita Pal1,2,3,4, Narmen Azazmeh1,2,3,4, Rumana Rashid9,10, Jia-Ren

Lin11, Margaret Cusick7, Abigail R. N. Reynolds1,2,4, Auriole C. R. Fassinou1,2,4, Georges Ayoub7,

Seth Malinowski7, Emily Lapinskas7, William Pisano7, John Jeang1,2,4, Sylwia A. Stopka12,

Michael S. Regan13, Johan Spetz14, Arati Desai15, Frank Lieberman16, Kamalakannan Palanichamy17, Joy D. Fisher8, Kristine Pelton7, Raymond Y. Huang12,Kristopher A. Sarosiek1,18, Louis B. Nabors19, Matthias Holdhoff8, Neeraja Danda20, Roy Strowd17,

Serena Desideri8, Tobias Walbert21, Xiaobu Ye8, Arnab Chakravarti22, Peter K. Sorger11,

Sandro Santagata9,11, Nathalie Y. R. Agar2,12,13, Stuart A. Grossman8, Brian M. Alexander23,

Patrick Y. Wen1,3,6§, Keith L. Ligon3,4,7,9,24§, Rameen Beroukhim1,2,3,4§

Science Translational Medicine 19 Feb 2025 Vol 17, Issue 786

https://www.science.org/doi/10.1126/scitranslmed.adn6274

Abstract

Inhibitors of murine double minute homolog 2 (MDM2) represent a promising therapeutic approach for the treatment of TP53 wild-type glioblastomas (GBMs), reactivating p53 signaling to induce cancer cell death. We conducted a surgical window-of-opportunity trial (NCT03107780) of the MDM2 inhibitor navtemadlin (KRT-232) in 21 patients with TP53 wild-type recurrent GBM to determine achievable drug concentrations within tumor tissues and biological mechanisms of response and resistance. Participants received navtemadlin at 120 mg (n = 10) or 240 mg (n = 11) for 2 days before surgical resection and after surgery until progression or unacceptable toxicity. Both 120 and 240 mg daily dosing achieved a pharmacodynamic impact, but median progression-free survival was 3.1 months. DNA sequencing of three recurrent tumors revealed an absence of TP53-inactivating mutations, indicating alternative mechanisms of resistance. To understand the mechanisms of response and resistance associated with navtemadlin, we conducted functional and spatial analyses of human tissue and patient-derived GBM neurosphere models. Navtemadlin induced partial tumor cell death as monotherapy, and combination with temozolomide enhanced apoptosis in GBM neurospheres while sparing normal bone marrow cells in vitro. We also observed up-regulation of oligodendrocyte differentiation genes with navtemadlin treatment and enrichment of oligodendrocyte transcription factor 2 (OLIG2)–positive cells at relapse, suggesting an unexplored mechanism of navtemadlin tolerance in GBM. Overall, these results indicated that clinically achievable doses of navtemadlin exert pharmacodynamic effects on GBM and suggest that combined treatment with temozolomide may be a route to more durable survival benefits.

(A) CONSORT diagram demonstrating the overall schematic for the ABTC-1604 clinical trial, which randomized surgically eligible patients with recurrent GBM to receive 120 or 240 mg of navtemadlin daily for 2 days before surgery, followed by surgical resection, followed by 240 mg of navtemadlin daily every 3 weeks after surgery if TP53 wild-type status was confirmed. (B) Timeline for enrolled patients, indicating the duration of radiation plus TMZ (RT + TMZ; yellow), adjuvant TMZ (purple), navtemadlin (red), and other (gray) or unknown (black line) treatments. The first nine patients had pretreatment- and on-navtemadlin–matched biopsies available for downstream analyses. (C) Kaplan-Meier curves of OS and PFS in the patient presurgical dose cohorts. (D) LC-MS/MS–derived pharmacokinetic data in contrast-enhancing tissues from patients receiving 120 mg (n = 7) or 240 mg (n = 8) of navtemadlin. (E) Microscopy and mass spectrometry images (left) of frozen tissue sections collected from two patients with TP53 wild-type (UP-1604-0230) and TP53 mutant (DF-1604-0123) GBM from specimens resected in magnetic resonance imaging contrast-enhancing (CE) and nonenhancing (NCE) tumor regions. Ion images of navtemadlin (m/z 301.051) and heme b (m/z 616.178) are displayed for each specimen. Bar graph (right) represents the average ion intensity across each tissue section.

Murine double minute homolog 2 (MDM2) 억제제는 TP53 야생형 교모세포종(GBM)의 치료에 있어 유망한 치료 접근법으로, p53 신호 경로를 재활성화하여 암세포 사멸을 유도하는 기전을 가진다. 우리는 MDM2 억제제인 navtemadlin (KRT-232)의 수술 전 투여(surgical window-of-opportunity) 임상시험(NCT03107780)을 TP53 야생형 재발성 GBM 환자 21명을 대상으로 실시하여, 종양 조직 내 약물 농도와 반응 및 내성의 생물학적 기전을 확인하고자 하였다.

참가자들은 수술 전 이틀간 navtemadlin을 120 mg(n=10) 또는 240 mg(n=11) 투여받았으며, 이후 수술 후에는 질병 진행 또는 불가피한 독성 발생 시점까지 투약을 지속하였다. 120 mg과 240 mg의 일일 투여는 모두 약력학적 영향을 유도했지만, 무진행 생존 기간(PFS)의 중앙값은 3.1개월이었다. 세 개의 재발성 종양에 대한 DNA 염기서열 분석 결과, TP53 불활성화 돌연변이는 발견되지 않아 내성의 다른 기전이 존재함을 시사하였다.

Navtemadlin에 대한 반응 및 내성과 관련된 메커니즘을 이해하기 위해, 우리는 인체 조직 및 환자 유래 GBM 신경구(neurosphere) 모델을 활용한 기능적 및 공간 분석을 수행하였다. Navtemadlin은 단독으로 부분적인 종양 세포 사멸을 유도했으며, 테모졸로마이드(temozolomide)와 병용 시 GBM 신경구에서 세포자멸사를 증가시키는 반면, 정상 골수 세포는 보존되었다. 또한 navtemadlin 치료 후 희소돌기세포 분화 관련 유전자(oligodendrocyte differentiation genes)의 발현 증가와 함께, 재발 시점에서 OLIG2 양성 세포(oligodendrocyte transcription factor 2-positive cells)의 풍부함이 관찰되어, navtemadlin 내성의 새로운 기전이 제시되었다.

전반적으로, 본 연구는 임상적으로 달성 가능한 navtemadlin 용량이 GBM에 약력학적 효과를 나타내며, 테모졸로마이드와의 병용 치료가 생존 혜택을 증대시킬 가능성이 있음을 시사한다.