Kummar, Shivaani

Abstract Background: Kinases from the SRC family of kinases (SFK) are predominantly inactive in non-cancerous cells and have been shown to be highly activated in tumor tissue. The role of SFKs in cell adhesion, invasion, proliferation, survival, and angiogenesis during tumor development has been extensively described. NXP900 is a novel, selective SFK inhibitor with low nanomolar potency against YES1 (0.47nM) and SRC (2.4nM). NXP900 has a unique binding mode of action (MOA), whereby it locks its target into its native “closed” conformation (type 1.5 inhibitor), resulting in inhibition of both the kinase and the scaffolding functions of the target kinase. This MOA differentiates NXP900 from other multi-kinase inhibitors, that, among other kinases, also inhibit the kinase activity of SFK targets. These multi-kinase inhibitors lock their targets in the active “open” conformation (type 1 inhibitors), and in the case of SFK targets, while this results in inhibition of the kinase activity, it also promotes the association of SFK with pro-cancer signaling partners. In addition, NXP900 is very selective, with minimal inhibitory activity against kinases outside the SFK. Methods: Study NXP900-101 (NCT05873686) is a first-in-human, Phase 1, dose escalation and expansion clinical trial of NXP900 in patients with advanced solid tumors. The primary objective of the study is to identify a dosing regimen with an acceptable safety profile and clinically relevant pharmacokinetics and pharmacodynamics (PK/PD) for additional clinical investigations. The key safety endpoints are estimation of the incidence and intensity of adverse events and identification of the highest tolerable dose. To characterize the PK/PD profile of NXP900, serial blood samples were collected after single and multiple doses of NXP900. Results: In 26 patients with advanced solid tumors treated with 20-200 mg/day NXP900, the median age was 61 years (range: 35-88), 65% were male and the median number of prior lines of anti-cancer therapy, including surgery, was 5. The most common treatment emergent adverse events (total incidence >20%) were largely reported as Grade 1-2 and included fatigue (42%, Grade 1-2: 91%), diarrhea (35%, Grade 1-2: 89%), nausea (31%, Grade 1-2: 100%), and dyspnea (23%, Grade 1-2: 67%). NXP900 exposure was dose proportional across the evaluated range (20-200 mg); following a single 200 mg oral dose, NXP900 demonstrated rapid absorption with median peak plasma concentration and terminal half-life of approximately 3 and 12 hours, respectively. Multiple dosing (20-200 mg daily) resulted in moderate drug accumulation. PD analysis showed that NXP900 potently inhibited the phosphorylation of SRC across a range of clinically relevant doses in peripheral blood mononuclear cells. Conclusions: In its first-in-human clinical trial in patients with advanced solid tumors NXP900 was biologically active with an acceptable safety profile, supporting its continued clinical development. Citation Format: Gerald Falchook, Jordi Rodon Ahnert, Shivaani Kummar, Hani M. Babikar, Stefan Symeonides, Mitesh J. Borad, Jason Henry, J. Mark Sloan, Justin L. Hay, Megan Sardone, Udai Banerji. First in human phase 1 trial of the SRC family kinase inhibitor NXP900 in patients with advanced solid tumors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_2):Abstract nr CT153.

Background Novel treatment options are required in patients with platinum-resistant ovarian cancer (PROC). Myeloid-derived suppressor cells promote a hostile tumor microenvironment and are associated with worse clinical outcomes in PROC. We evaluated the safety and preliminary efficacy of PY159, an agonist antibody to Triggering receptor expressed on myeloid cells-1 (TREM1) that reprograms immunosuppressive intratumoral myeloid cells, and PY314, an antagonist antibody to Triggering receptor expressed on myeloid cells-2 (TREM2) that depletes tumor-associated macrophages, as single agents and in combination with pembrolizumab in subjects with PROC. Methods PY159 and PY314 were individually evaluated in patients with PROC. Patients were treated with monotherapy (PY159 3 mg/kg or PY314 10 mg/kg), based on the recommended dose for expansion derived from the phase 1a studies. At the time of first progression, patients could continue study drug and crossover to combination therapy with pembrolizumab (200 mg) every 3 weeks at the discretion of the investigator. Disease assessment by Response Evaluation Criteria in Solid Tumor version 1.1 was performed every 6 weeks. Results 17 patients were enrolled in the PY159 study (median age 67, range 22–77; median prior therapies 6, range 2–18) and 16 patients in PY314 (median age 65.5, range 49–81; median prior therapies 4, range 2–10). 7 patients in PY159 and 8 patients in PY314 crossed over to combination therapy. Safety events included the following: treatment-related adverse events occurred in 15 patients (88.2%) in PY159 and 9 patients (56.3%) in PY314. Infusion-related reactions occurred in 6 patients (35.3%) in PY159 and 3 patients (18.8%) in PY314. Immune-related adverse events occurred in 13 patients (76.5%) in PY159 (arthralgias) and 1 patient (6.3%) in PY314 (diarrhea). Serious adverse events occurred in 6 patients (36.3%) in PY159 (1 related) and 12 patients (75%) in PY314 (all unrelated). The best radiographic response in PY159 was stable disease in 8/16 patients (50%; median 16 weeks, range 9–33), and in PY314, it was stable disease in 8/16 patients (50%; median 12 weeks, range 6–36). Median PFS was 2.76 months and 2.69 months in PY159 and PY314, respectively. There were no responses in the crossover arm. Conclusions Both PY159 and PY314 were well tolerated, with an acceptable safety profile, as both single agents and in combination with pembrolizumab. Both agents warrant further investigation in heavily pretreated PROC.

11505 Background: AL3818 (Catequentinib, Anlotinib) is a novel, orally administered, small molecule tyrosine kinase inhibitor. The primary objective of this Phase 3 study is to evaluate the efficacy of AL3818 monotherapy in patients (pts) with synovial sarcoma (SS) comparing with dacarbazine in randomization setting. Methods: Patients with a diagnosis of synovial sarcoma requiring second line or further line treatment were eligible for enrollment. The regimen was a 21-day cycle with oral AL3818 administered on 14 days on and 7 days off. This phase 3 trial is randomized in 2:1 ratio of AL3818 comparing to dacarbazine with option of crossover after PD of dacarbazine treatment. Progression free survival (PFS) with Log Rank test is the primary endpoint and this trial for SS is currently completed enrolled in US and Italy. Results: Total 79 pts initiated treatment and are evaluable, 52 received AL3818 as treatment arm (T), and 27 received dacarbazine (D) as control arm (C). Arms T/C median ages were 40.5/42.0 years (range: 18-70+) and 20/16 (38.5%/59.3%) were male. Overall, PFS was 2.89 months (95% CI: 2.73 – 6.87) for AL3818 and 1.64 (95% CI: 1.45 – 2.70) for D. The PFS of study met the primary endpoint with a p-value of 0.0015 and a HR of 0.449 (95% CI: 0.270– 0.744). At the month 4, 6, and 12, the percentages of progression free patients for AL3818 were 48.1%, 42.3% and 26.9%; and for D were 14.85%, 11.1% and 3.7%. For grade 3 treatment-related adverse events, 12(23.1%) of pts experienced for AL3818 and 7(25.9%) of pts experienced for D. The most common AL3818 related grade 3 AEs were diarrhea (5.8%) and hypertension (3.8%). Conclusions: This phase III trial demonstrates improved disease control and superior progression free survival for AL3818 vs dacarbazine in advanced SS. In addition, the study further confirms the acceptable benefit-risk profile of AL3818 from the prior randomized Phase 2b soft tissue sarcoma study (NCT02449343). AL3818 is a meaningful treatment option for pts with advanced SS. Clinical trial information: NCT 03016819 Clinical trial information: NCT03016819.

PURPOSE This trial assessed the utility of applying tumor DNA sequencing to treatment selection for patients with advanced, refractory cancer and somatic mutations in one of four signaling pathways by comparing the efficacy of four study regimens that were either matched to the patient's aberrant pathway (experimental arm) or not matched to that pathway (control arm). MATERIALS AND METHODS Adult patients with an actionable mutation of interest were randomly assigned 2:1 to receive either (1) a study regimen identified to target the aberrant pathway found in their tumor (veliparib with temozolomide or adavosertib with carboplatin [DNA repair pathway], everolimus [PI3K pathway], or trametinib [RAS/RAF/MEK pathway]), or (2) one of the same four regimens, but chosen from among those not targeting that pathway. RESULTS Among 49 patients treated in the experimental arm, the objective response rate was 2% (95% CI, 0% to 10.9%). One of 20 patients (5%) in the experimental trametinib cohort had a partial response. There were no responses in the other cohorts. Although patients and physicians were blinded to the sequencing and random assignment results, a higher pretreatment dropout rate was observed in the control arm (22%) compared with the experimental arm (6%; P = .038), suggesting that some patients may have had prior tumor mutation profiling performed that led to a lack of participation in the control arm. CONCLUSION Further investigation, better annotation of predictive biomarkers, and the development of more effective agents are necessary to inform treatment decisions in an era of precision cancer medicine. Increasing prevalence of tumor mutation profiling and preference for targeted therapy make it difficult to use a randomized phase II design to evaluate targeted therapy efficacy in an advanced disease setting.

Abstract Purpose: Romidepsin dosing recommendations for patients with malignancy and varying degrees of hepatic dysfunction was lacking at the time of regulatory approval for T-cell lymphoma. We conducted a multicenter phase I clinical trial (ETCTN-9008) via the NCI Organ Dysfunction Working Group to investigate safety, first cycle MTD, and pharmacokinetic profile of romidepsin in this setting. Patients and Methods: Patients with select advanced solid tumors or hematologic malignancies were stratified according to hepatic function. Romidepsin was administered intravenously on days 1, 8, and 15 of a 28-day cycle and escalation followed a 3 + 3 design in moderate and severe impairment cohorts. Blood samples for detailed pharmacokinetic analyses were collected after the first dose. Results: Thirty-one patients received one dose of romidepsin and were evaluable for pharmacokinetic analyses in normal (n = 12), mild (n = 8), moderate (n = 5), and severe (n = 6) cohorts. Adverse events across cohorts were similar, and dose-limiting toxicity occurred in two patients (mild and severe impairment cohorts). The MTD was not determined because the geometric mean AUC values of romidepsin in moderate (7 mg/m2) and severe (5 mg/m2) impairment cohort were 114% and 116% of the normal cohort (14 mg/m2). Conclusions: Data from the ETCTN-9008 trial led to changes in the romidepsin labeling to reflect starting dose adjustment for patients with cancer and moderate and severe hepatic impairment, with no adjustment for mild hepatic impairment.

5020 Background: V+C was well tolerated in a phase I trial and responses and prolonged disease stabilization were observed in BRCA + patients (pts).To assess the relative contribution of the PARP inhibitor to the efficacy observed for the combination, we conducted a randomized multicenter trial comparing the response rate (RR) of V and C to the RR of C alone in patients with deleterious BRCA mutations and recurrent ovarian, or primary peritoneal, fallopian tube or high-grade serous ovarian cancer. Methods: Pts were ≥ 18 yrs, KPS ≥ 70%, had adequate organ function, prior therapy with PARP inhibitors was allowed.Both drugs were administered orally qd; C 50 mg, V 60 mg; 21 day cycles. Pts were randomized to receive either C alone or V+C. At disease progression, pts on C alone were allowed to cross over to the combination. Radiologic imaging was performed at baseline and q 3 cycles for assessment of response. Dose reduction of V was allowed to 40 mg for gr 3 non-hematologic or gr 4 hematologic toxicities. The study design had an 88% power to detect the difference between a 15% RR for C alone versus 35% for V+C, early closure if fewer responses were observed on the combination arm in the first 65 pts enrolled (half of the total projected accrual). Results: Total of 74 pts were enrolled (36 pts C, 38 pts V+C), median age 58 (37-79 yrs), # of prior therapies: median 4 (1-9), 2 pts had prior PARP therapy. Treatment was well tolerated, Gr ≥ 2 toxicities per arm for initial regimen (# of pts): C alone: lymphopenia (2), mucositis (1); V+C: lymphopenia (4), anemia (2), leucopenia (2), neutropenia (2). Of the 74 pts evaluable for response at the interim analysis, 3 PRs observed in 36 pts on V+C and 5 PRs of 38 pts on C alone arm; thus accrual was stopped. PAR levels assessed by validated ELISA were inhibited (>80%) in PBMCs in 9/10 pts 4 hours post V, no inhibition with C alone. Conclusions: Addition of V, a PARP inhibitor, to C did not improve RR versus C alone. Exomic sequencing, gene expression studies, and Fanconi Anemia triple stain immunofluorescence (FATSI) assay for FancD2 nuclear foci formation using archival tissue are ongoing.