Damian, Silvia

Abstract Background PARP-1 has a well-established role in DNA repair. PARP-1 selective inhibitors are a new subclass of PARPi that offer potential for improved tolerability. NMS-03305293 (NMS-293) is an oral, brain-penetrant PARP-1 selective inhibitor with strong antitumor activity in BRCA mutated preclinical models. Furthermore, NMS-293 is synergistic with temozolomide (TMZ) in glioblastoma mouse models. Methods Two phase I/I-II dose-escalation/expansion studies assessed safety, tolerability, and preliminary antitumor activity of NMS-293. Both are actively recruiting. In PARPA-293-001 (NCT04182516), NMS-293 was administered orally, ranging from 20 mg (QD) to 160 mg (BID) for 21 or 28 days on 28-day cycle in adult patients with advanced/metastatic, relapsed/refractory solid tumors who have exhausted standard treatment options. In PARPA-293-002 (NCT04910022), NMS-293 was administered in a range of doses orally, QD or BID on days 1-7 plus TMZ 150mg/m2 QD on days 1-5 in repeated 28-day cycle in adult patients with recurrent diffuse gliomas. Tumor responses were measured by investigator-assessed RANO criteria. Results The unpooled safety database at the data-cut-off (02-AUG-23), includes 45 patients in PARPA-001 and 21 patients in PARPA-002. PARPA-001 showed an MTD of 100 mg BID for 28 days on a 28-day cycle, a dose with meaningful PK relative to preclinical activity. PARPA-002 dose finding is ongoing with no DLTs as of cutoff date. The most frequent (≥10%) any-grade treatment related adverse events (TRAEs) in PARPA-001 were reversible QTcF prolongation, nausea, asthenia, decreased appetite and vomiting, mainly mild/moderate. In PARPA-002, with discontinuous NMS-293 plus TMZ, no G≥3 TRAEs were reported. The most frequent (≥10%) any-grade TRAEs were: nausea, fatigue, vomiting, decreased appetite, and platelet count decreased, mainly G1 adverse events. Overall, no dose-dependent trends of myelosuppression have been observed. 14 recurrent glioma patients across dose levels in PARPA-002 were evaluable for tumor response. A patient with glioblastoma had confirmed partial response (PR) with duration 7.6+ weeks, remaining on treatment at cutoff date. A patient with grade 3 IDH-mutant astrocytoma had unconfirmed PR with ongoing tumor shrinkage at 16.1+ weeks. A patient with glioblastoma had complete radiological disappearance of enhancing non-target lesions, remaining on treatment at cutoff date. NMS-293 PK profiles showed an increase in exposure with the dose with approximately 5 to 13 hours half-life. Conclusion NMS-293, a PARP-1 selective, brain penetrant inhibitor was well tolerated in phase I clinical trials with no dose dependent trends of myelosuppression. Furthermore, NMS-293 showed encouraging clinical activity in combination with TMZ in difficult-to-treat recurrent glioma patients. Citation Format: Marjolein Geurts, Dorothee Gramatzki, Sara Merler, Matteo Duca, Fabio Girardi, Ugur T. Sener, Domenico Roberti, Grazia Saturno, Patrizia Crivori, Alessia Montagnoli, Lisa Mahnke, Siqing Fu, Paola Gaviani, Kurt A. Jaeckle, Jian Zhang, Yehui Shi, Valentina Guarneri, Michael Weller, Sani H. Kizilbash, Martin J. van den Bent, Michele Milella, Silvia Damian. Initial results from 2 Phase I studies of NMS-03305293, a selective PARP1 inhibitor [abstract]. In: Proceedings of the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics; 2023 Oct 11-15; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2023;22(12 Suppl):Abstract nr LB_A12.

PURPOSE The investigation of multiple molecular targets with next-generation sequencing (NGS) has entered clinical practice in oncology, yielding to a paradigm shift from the histology-centric approach to the mutational model for personalized treatment. Accordingly, most of the drugs recently approved in oncology are coupled to specific biomarkers. One potential tool for implementing the mutational model of precision oncology in daily practice is represented by the Molecular Tumor Board (MTB), a multidisciplinary team whereby molecular pathologists, biologists, bioinformaticians, geneticists, medical oncologists, and pharmacists cooperate to generate, interpret, and match molecular data with personalized treatments. PATIENTS AND METHODS Since May 2020, the institutional MTB set at Fondazione IRCCS Istituto Nazionale Tumori of Milan met weekly via teleconference to discuss molecular data and potential therapeutic options for patients with advanced/metastatic solid tumors. RESULTS Up to October 2021, among 1,996 patients evaluated, we identified >10,000 variants, 43.2% of which were functionally relevant (pathogenic or likely pathogenic). On the basis of functionally relevant variants, 711 patients (35.6%) were potentially eligible to targeted therapy according to European Society of Medical Oncology Scale for Clinical Actionability of Molecular Targets tiers, and 9.4% received a personalized treatment. Overall, larger NGS panels (containing >50 genes) significantly outperformed small panels (up to 50 genes) in detecting actionable gene targets across different tumor types. CONCLUSION Our real-world data provide evidence that MTB is a valuable tool for matching NGS data with targeted treatments, eventually implementing precision oncology in clinical practice.

PURPOSE This phase I/II study evaluated tremelimumab (anticytotoxic T-lymphocyte–associated antigen-4 monoclonal antibody) and durvalumab (antiprogrammed death ligand-1 monoclonal antibody) as monotherapies and in combination for patients with unresectable hepatocellular carcinoma (HCC), including a novel regimen featuring a single, priming dose of tremelimumab (ClinicalTrials.gov identifier: NCT02519348 ). PATIENTS AND METHODS Patients with HCC who had progressed on, were intolerant to, or refused sorafenib were randomly assigned to receive T300 + D (tremelimumab 300 mg plus durvalumab 1,500 mg [one dose each during the first cycle] followed by durvalumab 1,500 mg once every 4 weeks), durvalumab monotherapy (1,500 mg once every 4 weeks), tremelimumab monotherapy (750 mg once every 4 weeks [seven doses] and then once every 12 weeks), or T75 + D (tremelimumab 75 mg once every 4 weeks plus durvalumab 1,500 mg once every 4 weeks [four doses] followed by durvalumab 1,500 mg once every 4 weeks). Safety was the primary end point. Secondary end points included objective response rate (ORR) by Response Evaluation Criteria in Solid Tumors v1.1 and overall survival; exploratory end points included circulating lymphocyte profiles. RESULTS A total of 332 patients were enrolled (T300 + D, n = 75; durvalumab, n = 104; tremelimumab, n = 69; and T75 + D, n = 84). Tolerability was acceptable across arms, with grade ≥ 3 treatment-related adverse events occurring in 37.8%, 20.8%, 43.5%, and 24.4%, respectively. Confirmed ORRs (95% CI) were 24.0% (14.9 to 35.3), 10.6% (5.4 to 18.1), 7.2% (2.4 to 16.1), and 9.5% (4.2 to 17.9), respectively. An early expansion of CD8+ lymphocytes was associated with response across arms, with highest proliferating CD8+ lymphocyte levels occurring in the T300 + D arm. The median (95% CI) overall survival was 18.7 (10.8 to 27.3), 13.6 (8.7 to 17.6), 15.1 (11.3 to 20.5), and 11.3 (8.4 to 15.0) months in the T300 + D, durvalumab, tremelimumab, and T75 + D arms, respectively. CONCLUSION All regimens were found to be tolerable and clinically active; however, the T300 + D regimen demonstrated the most encouraging benefit-risk profile. The unique pharmacodynamic activity and association with ORR of the T300 + D regimen further support its continued evaluation in HCC.