Current State of Clinical Trials and Regulatory Approvals with Fibroblast Activation Protein Targeting Interventions.

In this article, the authors review the current state of fibroblast activation protein (FAP)-targeted interventions utilizing available data from clinicaltrials.gov. Thirty-seven records were reviewed and demonstrated interventions with imaging studies comprising the largest portion of the active studies in progress, followed by therapeutic studies using non-radioligand and radioligand therapy. The efforts are in early stages of clinical development; however the field is gaining significant momentum. Completion of existing clincial studies and entrance of new products into the clincial trial phase will shed important light on the clinical utility of these interventions and shape future clinical development efforts.

Phase 1 study of mTORC1/2 inhibitor sapanisertib (TAK-228) in advanced solid tumours, with an expansion phase in renal, endometrial or bladder cancer.

BACKGROUND: This Phase 1 dose-escalation/expansion study assessed safety/tolerability of sapanisertib, an oral, highly selective inhibitor of mTORC1/mTORC2, in advanced solid tumours. METHODS: Eligible patients received increasing sapanisertib doses once daily (QD; 31 patients), once weekly (QW; 30 patients), QD for 3 days on/4 days off QW (QD × 3dQW; 33 patients) or QD for 5 days on/2 days off QW (QD × 5dQW; 22 patients). In expansion cohorts, 82 patients with renal cell carcinoma (RCC), endometrial or bladder cancer received sapanisertib 5 mg QD (39 patients), 40 mg QW (26 patients) or 30 mg QW (17 patients). RESULTS: Maximum tolerated doses of sapanisertib were 6 mg QD, 40 mg QW, 9 mg QD × 3dQW and 7 mg QD × 5dQW. Frequent dose-limiting toxicities (DLTs) included hyperglycaemia, maculo-papular rash (QD), asthenia and stomatitis (QD × 3dQW/QD × 5dQW); expansion phase doses of 5 mg QD and 30 mg QW were selected based on tolerability beyond the DLT evaluation period. One patient with RCC achieved complete response; nine experienced partial responses (RCC: seven patients; carcinoid tumour/endometrial cancer: one patient each). Sapanisertib pharmacokinetics were time-linear and supported multiple dosing. Pharmacodynamic findings demonstrated treatment-related reductions in TORC1/2 biomarkers. CONCLUSIONS: Sapanisertib demonstrated a manageable safety profile, with preliminary antitumour activity observed in RCC and endometrial cancer. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, NCT01058707.

Phase I study of the investigational oral mTORC1/2 inhibitor sapanisertib (TAK-228): tolerability and food effects of a milled formulation in patients with advanced solid tumours.

BACKGROUND: Sapanisertib (TAK-228) is an investigational, orally available, potent and highly selective mTORC1/2 inhibitor demonstrating promise in numerous malignancies. This phase I study (NCT02412722) evaluated the safety, tolerability, pharmacokinetics and antitumour activity of single-agent TAK-228 (milled capsules), administered daily (QD) or weekly (QW) and in combination with paclitaxel in patients with advanced solid tumours. Pharmacokinetic comparisons of milled versus unmilled TAK-228 and the impact of food were also investigated. METHODS: Patients were enrolled to receive: TAK-228 QD, TAK-228 3 days/week plus paclitaxel 80 mg/m2 days 1, 8, 15 (TAK-228+P) or TAK-228 QW (all 28-day cycles); starting TAK­228 doses were 4, 6 and 20 mg, respectively. RESULTS: Sixty-one adults were enrolled. Maximum tolerated doses for milled TAK-228 were 3 mg (TAK-228 QD), 6 mg (TAK-228+P) and 30 mg (TAK-228 QW). Most patients reported ≥1 adverse event (AE); there were no meaningful differences in drug-related AEs across regimens or doses. Three on-study deaths occurred, all considered unrelated to study drugs. TAK-228 pharmacokinetics did not differ between unmilled/milled capsules or with/without paclitaxel. However, TAK-228 Cmax decreased by ~40% in fed versus fasted patients. Objective response rates were 12% (TAK-228 QD), 18% (TAK-228+P) and 0% (TAK-228 QW). One patient receiving TAK-228+P had a complete response; three patients receiving TAK-228+P and two patients receiving TAK-228 QD had partial responses. CONCLUSIONS: Milled TAK-228 was well tolerated with signs of antitumour activity; administration did not reduce overall exposure (area under the plasma concentration-time curve) but reduced Cmax, which is expected when dosed in the fed state. These promising findings warrant further investigation. TRIAL REGISTRATION NUMBER: NCT02412722.