Background: Pemigatinib is an oral, potent, selective fibroblast growth factor receptor (FGFR) 1-3 inhibitor. FIGHT-101, a three-part, open-label, first-in-human, phase I/II study (NCT02393248), evaluated pemigatinib in patients with advanced solid tumors. In parts 1 and 2, pemigatinib monotherapy had a manageable safety profile and antitumor activity in FGFR-altered tumors. Part 3 (pemigatinib combination therapies) results are presented here., Patients and Methods: Patients received 9, 13.5, or 20 mg oral once-daily pemigatinib on continuous or intermittent schedules with gemcitabine and cisplatin (pemi/gem/cis), docetaxel (pemi/doc), trastuzumab (pemi/tras), pembrolizumab (pemi/pembro), or retifanlimab (pemi/reti) irrespective of whether the tumor was confirmed as FGFR altered. Primary endpoints were safety and pharmacodynamics. Secondary endpoints were investigator-assessed tumor objective response rates (ORRs) and pharmacokinetics (PK)., Results: Of 65 enrolled patients (pemi/gem/cis, n = 8; pemi/doc, n = 7; pemi/tras, n = 6; pemi/pembro, n = 26; pemi/reti, n = 18), all discontinued. Treatment-emergent adverse events (TEAEs) were generally consistent with individual drug AEs. Serious and grade ≥3 TEAEs occurred in 0%-85.7% and 33.3%-100.0% of patients across treatment groups, respectively. All pemigatinib combinations demonstrated steady-state PK comparable to monotherapy. Pharmacodynamic effects in all pemigatinib combinations, except pemi/gem/cis, were consistent with monotherapy. Less inhibition of FGFR2α phosphorylation was observed with this combination. ORRs (95% confidence interval) were 37.5% [8.5% to 75.5% (pemi/gem/cis)], 14.3% [0.4% to 57.9% (pemi/doc)], 0% (pemi/tras), 26.9% [11.6% to 47.8% (pemi/pembro)], and 11.1% [1.4% to 34.7% (pemi/reti)]. All groups had instances of tumor shrinkage. ORRs in assessable patients with FGFR rearrangements and mutations were 50% and 33%, respectively., Conclusions: Pemigatinib combination therapy showed no unexpected toxicities. PK and pharmacodynamics were mostly consistent with pemigatinib monotherapy. Pemi/gem/cis (37.5%) and pemi/pembro (26.9%) had the highest ORR; most responders had FGFR alterations., Competing Interests: Disclosure VS reports scientific advisory board participation for Relay Therapeutics, Incyte, Novartis, Eli Lilly/Loxo Oncology, Roche, Pfizer, Jazz Pharmaceuticals, Bayer, AbbVie, Regeneron, Novartis, Clinical Care Communications, Invited Speaker. KPP reports consulting or advisory roles for Basilea and Turning Point Therapeutics and research funding paid to the institution from 3D Medicines, AbbVie, ADC Therapeutics, Amgen, Anheart Therapeutics, Bayer, Calithera Biosciences, Daiichi Sankyo, EMD Serono, F-star, Incyte, Jounce Therapeutics, Lilly, Linnaeus Therapeutics, MabSpace Biosciences, MedImmune, Merck, Mersana, Mirati Therapeutics, Peloton Therapeutics, Pfizer, Regeneron Pharmaceuticals, Inc., Syros Pharmaceuticals, Tempest Therapeutics, and Treadwell Therapeutics. DM received consulting fees from AbbVie, Arcus, Lilly, and Mirati. Research grants or funds were received from AstraZeneca, Bristol Myers Squibb, Boehringer Ingelheim, Epicentrx, Incyte, Lilly, Merck, Novartis, Pfizer, Roche, Surface, and Y-mabs. NBM received research funding paid directly to the institution from Actuate Therapeutics, Amphivena Therapeutics, Aravive Inc., AstraZeneca, BioMed Valley Discoveries, Compass Therapeutics, Erytech Pharma, Genentech, Incyte, Leap Therapeutics, Merck Sharp and Dohme, Mereo BioPharma Group, NuCana, Repare Therapeutics, and Syros Pharmaceuticals. IS received research funding paid directly to the institution from Alligator Bioscience, AstraZeneca, Bristol Myers Squibb, Cantargia AB, Genentech, Genmab, Incyte, Loxo/Bayer, Loxo/Lilly, MSD, Novartis, Orion, Roche, Pfizer, Puma Biotechnology, and Symphogen; and support for attending meetings and/or travel expenses from AstraZeneca, Incyte, Merck, and Pfizer. MLV and CT are employees and shareholders of Incyte. IMS was an employee of Incyte at the time of the study. MG is a speaker for Guardant and a consultant for Cellularity, Merck, and Sanofi. All other authors have declared no conflicts of interest., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)