Background and Objective Gilteritinib is a novel, highly selective tyrosine kinase inhibitor approved in the USA, Canada, Europe, Brazil, Korea, and Japan for the treatment of FLT3 mutation-positive acute myeloid leukemia. This article describes the clinical pharmacokinetic profile of gilteritinib. Methods The pharmacokinetic profile of gilteritinib was assessed from five clinical studies. Results Dose-proportional pharmacokinetics was observed following once-daily gilteritinib administration (dose range 20-450 mg). Median maximum concentration was reached 2-6 h following single and repeat dosing of gilteritinib; mean elimination half-life was 113 h. Elimination was primarily via feces. Exposure to gilteritinib was comparable under fasted and fed conditions. Gilteritinib is primarily metabolized via cytochrome P450 (CYP) 3A4; coadministration of gilteritinib with itraconazole (a strong P-glycoprotein inhibitor and CYP3A4 inhibitor) or rifampicin (a strong P-glycoprotein inducer and CYP3A inducer) significantly affected the gilteritinib pharmacokinetic profile. No clinically relevant interactions were observed when gilteritinib was coadministered with midazolam (a CYP3A4 substrate) or cephalexin (a multidrug and toxin extrusion 1 substrate). Unbound gilteritinib exposure was similar between subjects with hepatic impairment and normal hepatic function. Conclusions Gilteritinib exhibits a dose-proportional pharmacokinetic profile in healthy subjects and in patients with relapsed/refractory acute myeloid leukemia. Gilteritinib exposure is not significantly affected by food. Moderate-to-strong CYP3A inhibitors demonstrated a significant effect on gilteritinib exposure. Coadministration of gilteritinib with CYP3A4 or multidrug and toxin extrusion 1 substrates did not impact substrate concentrations. Unbound gilteritinib was comparable between subjects with hepatic impairment and normal hepatic function; dose adjustment is not warranted for patients with hepatic impairment.

Background: Gilteritinib, an oral FMS-like tyrosine kinase 3 (FLT3) inhibitor, demonstrated antileukemic responses in patients with FLT3-mutated (FLT3mut+) relapsed/refractory acute myeloid leukemia (AML). We report final results from a phase 1 study of once-daily oral gilteritinib plus intravenous (IV) chemotherapy in patients with newly diagnosed AML. Methods: This 4-part, open-label, phase 1 study (NCT02236013) assessed the safety/tolerability and antileukemic effects of gilteritinib plus 7+3 induction and high-dose cytarabine consolidation chemotherapy, and as single-agent maintenance therapy in adults with newly diagnosed AML. In part 1, successive cohorts of 3-6 patients received 40-200 mg/d gilteritinib (Days 4-17) and ≤2 cycles of induction (cytarabine 100 mg/m2/d IV, Days 1-7; idarubicin 12 mg/m2/d IV, Days 1-3). In part 2, patients (n=33, of which at least 15 were FLT3mut+) received the recommended 120 mg/d gilteritinib expansion dose and ≤2 cycles of the part 1 induction schedule. In part 3, patients were stratified into 2 cohorts: one receiving treatment from part 2 (n=7) and the other receiving treatment that replaced idarubicin with daunorubicin (90 mg/m2/d IV, Days 1-3; n=7). In part 4, patients (n=12) received the same induction as the part 3/daunorubicin cohort (with a reduction in cycle 2 to daunorubicin 45 mg/m2/d). During consolidation, patients received ≤3 cycles of cytarabine (1.5 g/m2 every 12 hours; Days 1, 3, and 5) and gilteritinib (Days 1-14 for parts 1-3; Days 1-56 for part 4) at the induction dose. Gilteritinib was given once daily in 28-day cycles for up to 26 cycles as maintenance therapy (maintenance phase is still ongoing). Patients achieving composite complete remission (CRc) or partial remission could undergo hematopoietic stem cell transplant (HSCT) and resume maintenance gilteritinib treatment post-HSCT. Results: As of 23 June 2020, 80 patients were allocated to treatment (safety analysis set, n=79); median age was 59.0 y (range, 23-77) and most were male (62.0%). Median follow-up for overall survival (OS) was 35.8 mo. Dose-limiting toxicities are provided in Table 1. The maximum tolerated dose was 120 mg/d. Serious treatment-related adverse events (AEs) and AEs leading to discontinuation of gilteritinib occurred in 12.7% (n=10) and 5.1% (n=4) of patients, respectively. One (1.3%) death occurred across all treatment phases. Grade ≥3 nonhematologic AEs (≥10% of patients) were increased alanine aminotransferase (13.9%), pneumonia (13.9%), sepsis (11.4%), and bacteremia (11.4%). At the end-of-induction time point, there were 44 (55.7%) total FLT3mut+ patients across all dose groups and 38 (48.1%) patients who received gilteritinib 120 mg/d. Investigator-reported CRc was achieved by 81.8% of patients across all dose groups (n=36) and 81.6% among patients who received gilteritinib 120 mg/d (n=31; Table 2). Anthracycline choice had no clear impact on CRc rate, although the number of patients in these cohorts was low. In FLT3mut+ patients who achieved CRc in any dose group, median (95% CI) duration of CRc and disease-free survival were 14.1 (4.0-29.9) and 15.3 (9.8-not reached) mo, respectively. Median OS for FLT3mut+ patients has not been reached. The survival probability (95% CI) in all FLT3mut+ patients at weeks 8, 12, 26, 52, and 104 were 97.7% (84.6%-99.7%), 95.3% (82.5%-98.8%), 92.9% (79.6%-97.7%), 83.1% (67.7%-91.5%), and 71.8% (54.6%-83.4%), respectively. In patients with FLT3 internal tandem duplication (ITD)-positive AML achieving CRc, mutational clearance (summed FLT3 ITD signal ratio of ≤10-4 after induction or consolidation) was achieved by 70% (n/N=16/23) of patients receiving a gilteritinib dose of ≥120 mg. HSCT occurred in 30.4% of the total population (n/N=24/79). Analysis of plasma inhibitory activity and pharmacokinetics of gilteritinib will be available at presentation. Conclusions: Gilteritinib plus induction and consolidation chemotherapy is well tolerated in patients with newly diagnosed AML. Favorable antileukemic responses were observed in FLT3mut+ patients regardless of anthracycline type or gilteritinib administration schedule, with a mutational clearance rate of 70.0%. Based on these results, randomized clinical trials of induction and consolidation chemotherapy plus gilteritinib vs midostaurin in FLT3mut+ AML patients have been initiated. Disclosures Pratz: AbbVie: Other: Scientific Advisory Board, Research Funding; Astellas: Other: Scientific Advisory Board, Research Funding; Boston BioMedical: Consultancy; Celgene: Other: Scientific Advisory Board; Agios: Other: Scientific Advisory Board, Research Funding; Jazz Pharmaceutical: Consultancy; Millennium: Research Funding; Daiichi Sankyo: Research Funding. Cherry:Pfizer: Other: Advisory Board; BMS: Other: Advisory Board; Kite: Other: Advisory Board. Altman:PeerView: Consultancy; ASH: Consultancy; Syros: Consultancy; Janssen: Consultancy; Genentech: Research Funding; Amphivena: Research Funding; Amgen: Research Funding; Aprea: Research Funding; ImmunoGen: Research Funding; Celgene: Research Funding; Boehringer Ingelheim: Research Funding; PrIME Oncology: Consultancy; Immune Pharmaceuticals: Consultancy; Novartis: Consultancy; Glycomimetics: Other: Data safety and monitoring committee; Daiichi Sankyo: Other: Advisory Board - no payment but was reimbursed for travel; Kura Oncology: Other: Scientific Advisory Board - no payment accepted, Research Funding; Kartos: Research Funding; AbbVie: Other: advisory board, Research Funding; Fujifilm: Research Funding; BioSight: Other: No payment but was reimbursed for travel , Research Funding; Bristol-Myers Squibb: Consultancy; Astellas: Other: Advisory Board, Speaker (no payment), Steering Committee (no payment), Research Funding; Cancer Expert Now: Consultancy; Agios: Other: advisory board, Research Funding; Theradex: Other: Advisory Board; France Foundation: Consultancy. Cruz:Takeda: Speakers Bureau. Jurcic:Celgene: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; BMS: Consultancy, Research Funding; Daiichi-Sankyo: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees; Arog Pharmaceuticals: Research Funding; Astellas: Research Funding; Forma Therapeutics: Research Funding; Genentech: Research Funding; Kura Oncology: Research Funding; PTC Therapeutics: Research Funding; Syros Pharmaceuticals: Research Funding; AbbVie: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding. Levis:Menarini: Honoraria; Amgen: Honoraria; FujiFilm: Honoraria, Research Funding; Daiichi-Sankyo: Honoraria; Astellas: Honoraria, Research Funding. Lin:Pfizer: Research Funding; Bio-Path Holdings: Research Funding; Abbvie: Research Funding; Seattle Genetics: Research Funding; Tolero Pharmaceuticals: Research Funding; Ono Pharmaceutical: Research Funding; Prescient Therapeutics: Research Funding; Incyte: Research Funding; Genetech-Roche: Research Funding; Gilead Sciences: Research Funding; Aptevo: Research Funding; Celyad: Research Funding; Celgene: Research Funding; Astellas Pharma: Research Funding; Mateon Therapeutics: Research Funding; Jazz: Research Funding; Trovagene: Research Funding. Perl:Bayer HealthCare Pharmaceuticals: Research Funding; Syndax: Consultancy, Honoraria; Jazz: Honoraria, Other; Arog Pharmaceuticals Inc: Other: uncompensated consulting, travel costs for meetings; Biomed Valley Discoveries: Research Funding; Agios: Consultancy, Honoraria, Other; FUJIFILM Pharmaceuticals USA, Inc: Research Funding; AbbVie Inc: Consultancy, Honoraria, Other, Research Funding; Loxo Oncology Inc, a wholly owned subsidiary of Eli Lilly & Company: Consultancy, Honoraria, Other; Takeda: Honoraria, Other: Travel costs for meeting; Astellas: Consultancy, Honoraria, Other: writing/editorial support, travel costs for meeting presentations related to study, Research Funding; Leukemia & Lymphoma Society, Beat AML: Consultancy; New Link Genetics: Honoraria, Other; Daiichi Sankyo: Consultancy, Honoraria, Other: Writing/editorial support, travel costs for meetings, Research Funding; FORMA Therapeutics: Consultancy, Honoraria, Other; Actinium Pharmaceuticals Inc: Consultancy, Honoraria, Research Funding; Novartis: Honoraria, Other, Research Funding. Podoltsev:Arog Pharmaceuticals: Research Funding; Astex Pharmaceuticals: Research Funding; Jazz Pharmaceuticals: Research Funding; Sunesis Pharmaceuticals: Research Funding; Boehringer Ingelheim: Research Funding; Daiichi Sankyo: Research Funding; Astellas Pharma: Research Funding; CTI biopharma: Consultancy, Honoraria, Research Funding; Bristol-Myers Squib: Consultancy, Honoraria; Genentech: Research Funding; Novartis: Consultancy, Honoraria; Celgene: Consultancy, Honoraria, Research Funding; Samus Therapeutics: Research Funding; Agios Pharmaceuticals: Consultancy, Honoraria; Pfizer: Consultancy, Honoraria, Research Funding; Incyte: Consultancy, Honoraria; Blueprint Medicines: Consultancy, Honoraria; Alexion: Consultancy, Honoraria; Kartos Therapeutics: Research Funding; AI Therapeutics: Research Funding. Schiller:Abbvie: Research Funding; Actinium: Research Funding; Ariad: Research Funding; Amgen: Consultancy, Current equity holder in publicly-traded company, Research Funding, Speakers Bureau; AstraZeneca: Consultancy; Incyte: Consultancy, Research Funding, Speakers Bureau; Novartis: Consultancy, Research Funding; Ono Pharma: Consultancy; Kite Pharma: Research Funding; Stemline: Speakers Bureau; Gilead: Speakers Bureau; Celgene: Research Funding, Speakers Bureau; Sanofi: Speakers Bureau; Agios: Consultancy, Research Funding, Speakers Bureau; DeltaFly: Research Funding; Deciphera: Research Funding; Daiichi Sankyo: Research Funding; Cyclacel: Research Funding; Constellation: Research Funding; Celator: Research Funding; Astellas Pharma: Honoraria, Research Funding; Bristol-Myers Squibb: Current equity holder in publicly-traded company, Research Funding; Forma: Research Funding; FujiFilm: Research Funding; Gamida: Research Funding; Genentech-Roche: Research Funding; Geron: Research Funding; Jazz Pharmaceuticals: Research Funding; Karyopharm: Research Funding; Mateon: Research Funding; MedImmune: Research Funding; Onconova: Research Funding; Pfizer: Current equity holder in publicly-traded company, Research Funding; Regimmune: Research Funding; Samus: Research Funding; Sangamo: Research Funding; Tolero: Research Funding; Trovagene: Research Funding; Kaiser Permanente: Consultancy; Johnson & Johnson: Current equity holder in publicly-traded company. Hill:Targeted Molecular Diagnostics: Patents & Royalties: US7862995; Astellas: Current Employment; Ligacept, LLC: Current equity holder in publicly-traded company, Patents & Royalties: US9051388, US9683222. James:Astellas: Current Employment. Lu:Astellas: Current Employment. Tiu:Astellas Pharma Global Development: Current Employment; Eli Lilly & Company: Current equity holder in publicly-traded company, Ended employment in the past 24 months. OffLabel Disclosure: New Indication

2606 Background: CC-223 is an ATP-competitive inhibitor of the mTOR kinase, including both TORC1 and TORC2. CC-223 was selected to address resistance of rapamycin analogues mediated by TORC2 activation. Methods: Following establishment of the MTD (reported at ASCO 2012), subjects with select advanced, refractory solid tumors, including NSCLC, HCC, NET, GBM and breast were enrolled in expansion cohorts of up to 20 evaluable subjects. CC-223 was dosed at 45 mg once daily in 28 day cycles until disease progression. Results: As of 09 January, 2013, 101 solid tumor subjects have been treated, including NSCLC (26), HCC (25), NET (23), breast (14), and GBM (13). Results from the NSCLC, HCC, and GBM cohorts are reported here; NET results are reported separately. The most common (> 20%) related adverse events (all grades) were fatigue, rash, stomatitis, hyperglycemia, anorexia, nausea, vomiting and diarrhea. In addition, related serious adverse events included infection (1), pneumonitis (4), renal insufficiency (2) and pancreatitis (2). CC-223 dose reduction was required in > 50% of subjects with NSCLC and HCC, usually during cycle 1 or 2. Exposure-dependent TORC1 (p4EBP1) and TORC2 (pAKT) inhibition was observed across cohorts. mTOR pathway inhibition and/or decreased proliferation was demonstrated in paired tumor biopsies, but results were inconsistent. Reduction in glucose uptake (> 25% decrease in SUV) on PET imaging at day 15 was observed in 78% (14/18) of NSCLC and 69% (11/16) of HCC subjects. Partial tumor responses were observed in evaluable subjects with NSCLC (1/17; confirmed, treatment duration 36 weeks) and HCC (3/15; 1 confirmed, treatment duration 15 – 26 weeks). Disease control rate in the overall NSCLC cohort was 42% (11/26) and in the HCC cohort, 40% (10/25). GBM subjects underwent salvage resections on study and none were progression-free at 6 months. CC-223 was present in all (11/11) resected GBM tumors with plasma:tumor ratios of 16 - 77%, confirming transit across the blood-brain barrier. Conclusions: Encouraging signals of biomarker and clinical activity were observed in HCC and NSCLC. Due to the frequency of dose reductions, select additional cohorts will be enrolled at a starting dose of 30 mg QD. Clinical trial information: NCT01177397.

TPS7067 Background: FLT3 mutations occur in 30% of patients with acute myeloid leukemia (AML), most often as internal tandem duplications (FLT3-ITD) or point mutations at codon D835. FLT3-ITDs are associated with high relapse rates, short remission duration, and poor overall survival (OS); FLT3-D835 can confer resistance to other tyrosine kinase inhibitors (TKIs). Gilteritinib is a highly selective FLT3/AXL TKI with activity against both FLT3-ITD and FLT3-D835 mutations. A recent phase 1/2 study of gilteritinib (20–450 mg/d) in relapsed/refractory (R/R) AML showed favorable tolerability at doses ≤300 mg/d, and consistent, potent FLT3 inhibition at doses ≥80 mg/d. Patients with FLT3 mutation-positive (FLT3mut+) AML receiving doses ≥80 mg/d had an ORR of 52% (CR/CRp/CRi = 41%, PR = 11%) and longer OS than historic experience in R/R AML with combination cytotoxic chemotherapy or other FLT3 TKIs as monotherapy. Given these results, we initiated a phase 3 trial of once-daily (QD) 120 mg gilteritinib. Methods: This randomized, open-label phase 3 study (NCT02421939) will enroll 369 adults with FLT3mut+ AML in first relapse or refractory to front-line therapy. Patients who have not previously received FLT3 inhibitors, except sorafenib and midostaurin, will be randomized 2:1 to either 120 mg gilteritinib QD or the investigator’s pre-randomization specified salvage chemotherapy choice (LoDAC, Aza, MEC, FLAG-IDA), and stratified by prior chemotherapy response and salvage chemotherapy intensity. Gilteritinib or low-intensity chemotherapy cohorts will receive continuous 28-day treatment cycles until a discontinuation event occurs; the high-intensity chemotherapy cohort will receive ≤2 treatment cycles before response measurement. Primary objective is OS; key secondary objectives are event-free survival and CR rate. Other secondary objectives: leukemia-free survival, remission duration, composite CR rate, subsequent transplantation rate, patient-reported fatigue, and safety. A formal interim analysis is planned when ~50% of planned death events have occurred. Study enrollment began on Oct 23, 2015; as of Jan 20, 2017, 167 subjects have been randomized. Clinical trial information: NCT02421939.

Background: CC-122 is a novel non-phthalimide analog of the IMiDs® immunomodulatory drugs (lenalidomide and pomalidomide) and a first in class PPMTM (Pleiotropic Pathway Modifier) compound with multiple biological activities including potent anti-proliferative activity against B-lineage cells (10-fold greater than lenalidomide), anti-angiogenic activity (100-fold greater than lenalidomide) and immunomodulatory effects (10-fold greater than lenalidomide). The molecular target of CC-122 is cereblon (CRBN), a substrate receptor of the Cullin ring E3 ubiquitin ligase complex (CRL4CRBN). CC-122 promotes ubiquitination of lymphoid transcription factors Ikaros (IKZF1) and Aiolos (IKZF3) in a CRBN-dependent manner, leading to their subsequent degradation. Following establishment of 3mg once daily (QD) as the maximum tolerated dose (Blood 122:2905 2013), patients with advanced aggressive non-Hodgkin lymphoma (NHL), multiple myeloma (MM), and select solid tumors were enrolled in parallel expansion cohorts of up to 20 evaluable patients. CC-122 was dosed at 3 mg QD in 28-day cycles until disease progression. Results: As of May 1, 2014, 93 total patients were enrolled in the expansion phase of the study. The NHL cohort included 21 patients with diffuse large B-cell lymphoma (DLBCL) and 1 patient with mantle cell lymphoma, and twenty-four patients were enrolled in the MM cohort. Results in solid tumor cohorts will be reported separately. All patients were ECOG performance status 0-2, the median number of prior systemic therapies was 4 (NHL) and 6 (MM). The most common (> 20%) adverse events (AEs) (grades 1-4) included neutropenia (69.6%), anemia (52%), asthenia (50%), pyrexia (35%), diarrhea (30%), cough (30%), thrombocytopenia (28%), and constipation (22%). Grade 3/4 AEs occurring in more than one patient were neutropenia (52%), anemia (26%), febrile neutropenia (13%), and thrombocytopenia (7%). CC-122 dose reduction was required in 36.4% of patients with NHL and 63% of patients with MM, the majority of which was due to neutropenia and occurred during cycle 1 or 2. CC-122 systemic exposure in NHL and MM patients was generally comparable after administration of single and multiple doses. Peak concentrations were observed between 30 minutes and 2 hours (median Tmax concentration = 1.5 h). Four treated patients with DLBCL had objective responses; one patient with complete response (CR) and 3 with partial responses (PR). Responses were observed in patients with germinal center B cell (GCB), non-GCB and Myc/Bcl2 over-expressing DLBCL. Four treated patients with MM had PR, and two of these responders were progression free beyond 10 cycles. A single dose of CC-122 3mg resulted in decreased Aiolos protein expression at 1.5 and 5 hours compared with baseline in peripheral B cells (median 38% and 53%) and T cells (median 31% and 54%) in the combined NHL (n = 16) and MM (n = 19) cohorts. Decrease in expression of Aiolos protein from baseline was also observed in lymph node biopsies of patients with DLBCL. Furthermore, CC-122 treatment decreased CD19+ B cells (median = 57% of baseline), expanded CD4-/CD8+/CD45RA-/CD45RO+ cytotoxic memory T cells (median = 320% of baseline), and expanded CD4+/CD8-/CD45RA-/CD45RO+ helper memory T cells (median = 154% of baseline) in peripheral blood samples from patients with MM (n = 9) and NHL (n = 3-12) subjects. Additionally, ex vivo activation of T cells after a single dose of CC-122 compared with baseline, as measured by IL-2 production, increased by a median of 776% (NHL n = 3 and MM n = 7). Conclusions: CC-122 shows promising initial clinical and pharmacodynamic activity in heavily pretreated relapse/refractory NHL and MM patients. Biomarker analysis indicates that the 3 mg QD dose of CC-122 results in rapid CRBN target engagement and Aiolos degradation in the peripheral blood lymphocytes of patients with NHL and MM patients and in NHL tumor tissue. Exploration of an intermittent dosing to mitigate neutropenia-related dose reductions and interruptions is ongoing and clinical studies exploring drug combinations with CC-122 are underway. Disclosures Ribrag: Celgene Corp: Consultancy. Rasco:Celgene Corp: Membership on an entity's Board of Directors or advisory committees. Wei:Celgene Corp: Employment, Equity Ownership. James:Celgene Corp: Employment. Hagner:Celgene Corp: Employment, Equity Ownership. Gandhi:Celgene Corp: Employment, Equity Ownership. Chopra:Celgene Corp: Employment, Equity Ownership. DiMartino:Celgene Corp: Employment, Equity Ownership. Pourdehnad:Celgene Corp: Employment, Equity Ownership. Stoppa:Celgene Jansen: Honoraria.