Search

Fibroblast growth factor receptor 2 (FGFR2) is associated with an unfavorable prognosis in patients with gastric cancer. Acquired mutations in FGFR2 develop resistance to multikinase inhibitors. Besides, resistance to monoclonal antibodies depends on the type of FGFR2 isoforms IIIc or IIIb expressed by cancer cells. Alofanib (RPT835) is a small molecule, allosteric inhibitor that binds to the non-active site of FGFR2 extracellular domain. RPT835GC1B (NCT04071184) is an ongoing Phase 1b open-label study evaluating the safety and preliminary efficacy of alofanib in patients with metastatic gastric adenocarcinoma pretreated with ≥ 1 previous lines of therapy. The standard dose-escalation part (design 3+3) aims to establish the maximum tolerated dose (MTD) or recommended phase 2 dose (R2PD) as a primary endpoint. The first part of the study includes a 28-day period when alofanib is administered daily intravenously for 5-days followed by a 2-day interval (rest). There are five dose levels: 50, 100, 165, 250, and 350 mg/m2. Secondary endpoints include pharmacokinetic (PK) parameters, rate of adverse events, progression-free survival (PFS), overall survival (OS), and objective response rate. All patients received alofanib until disease progression or unacceptable toxicity. As of data cutoff on December 30, 2020, 13 patients have been enrolled in the trial. Patients were predominantly male (85%), 54% had 2 and more metastatic sites, including liver metastases (54%), and were heavily pretreated (60% received previous 3-6 lines of therapy). To date, all enrolled patients have been studied for safety and have not experienced any dose-limiting toxicities (DLTs) within the 28-day DLT-assessment window. Grade 3 or higher drug related adverse events have included raised ALT/AST at 50 mg/m2, diarrhea at 165 mg/m2, and hyponatremia at 350 mg/m2. 93% of patients had any grade adverse events. Most common Grade 1-2 adverse events included fatigue, diarrhea, nausea, anemia, thrombocytopenia, increased alkaline phosphatase, and reactions immediately after intravenous injections (facial flushing, dizziness, weakness, sweating, and sinus tachycardia). Grade 1 hyperphosphatemia was founded in 25% of cases. One patient discontinued treatment due to drug related Grade 3 uncontrolled diarrhea. Alofanib has demonstrated evidence of biologic activity in 12 patients in the first 4 dose levels evaluated to date. Disease control rate was 75% (1 durable partial response (13 months) at 50 mg/m2 and 8 stable diseases at 50-250 mg/m2). After a median follow-up of 4.5 months, the median PFS and OS was not reached. In conclusion, dosing up to 350 mg/m2 of alofanib was well tolerated, DLT and MTD were not reached. The early biologic activity of alofanib in the late-line treatment of metastatic gastric cancer is encouraging. In addition to the above, any updated safety, PK, and efficacy data will be presented at the time of the AACR meeting. Citation Format: Ilya Tsimafeyeu, Galina Statsenko, Anastasia Mochalova, Natalia Trenina, Vyacheslav Kurakin, Natalia Besova, Kristina Novoselova, Natalia Abramova, Ekaterina Obarevich, Alina Kashanova, Margarita Suetina, Vladimir Moiseyenko, Mikhail Byakhov, Elena Artamonova, Liubov Vladimirova, Sergei Tjulandin. Preliminary data on a phase 1b, first-in-human study of the allosteric extracellular FGFR2 inhibitor alofanib in patients with refractory metastatic gastric cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr CT113.

Alofanib (RPT835) is a novel selective allosteric inhibitor of fibroblast growth factor receptor 2 (FGFR2). We showed previously that alofanib could bind to the extracellular domain of FGFR2 and has an inhibitory effect on FGF2-induced phoshphorylation of FRS2α. In the present study, we further showed that alofanib inhibited phosphorylation of FRS2α with the half maximal inhibitory concentration (IC50) values of 7 and 9 nmol/l in cancer cells expressing different FGFR2 isoforms. In a panel of four cell lines representing several tumour types (triple-negative breast cancer, melanoma, and ovarian cancer), alofanib inhibited FGF-mediated proliferation with 50% growth inhibition (GI50) values of 16-370 nmol/l. Alofanib dose dependently inhibited the proliferation and migration of human and mouse endothelial cells (GI50 11-58 nmol/l) compared with brivanib and bevacizumab. Treatment with alofanib ablated experimental FGF-induced angiogenesis in vivo. In a FGFR-driven human tumour xenograft model, oral administration of alofanib was well tolerated and resulted in potent antitumour activity. Importantly, alofanib was effective in FGFR2-expressing models. These results show that alofanib is a potent FGFR2 inhibitor and provide strong rationale for its evaluation in patients with FGFR2-driven cancers.

e15659 Background: The incidence of cancer among the people of reproductive age is constantly increasing. Although FGF2/FGFR2 expression in the male reproductive tract has been reported, there is no evidence of the impact of FGFRs inhibitors on sperm function. Therefore, the objective of this large study was to determine the effects of alofanib, selective FGFR2 allosteric extracellular inhibitor on the regulation of sperm physiology using the rat and rabbit models. Methods: Two-hundred forty Sprague-Dawley rats and 30 Chinchilla white rabbits received alofanib (0–40.5 and 0–21.6 mg/kg/day, respectively) intravenously on a consecutive daily dosing schedule for six months. Eighty rats and 8 rabbits were in the control group. The subchronic study evaluated high doses (300 mg/kg/day) of alofanib for 2 months in 15 male rats. Necropsy was conducted following treatment/recovery periods, and histologic examinations were performed. Results: Animals were active. After injections of a dose equivalent to a human therapeutic dose during 6 months, most of the seminiferous tubules were empty, the elements of spermatogenesis were not classified, and altered primary spermatogonia and spermatocytes were distinguished in male rats. After injections of a five-fold dose, all seminiferous tubules were empty and expelled by a cylindrical epithelium. Very similar changes in sperm physiology were founded in rabbits. Most of the seminiferous tubules were blank, and some tubules contained eosinophilic amorphous masses. High doses of alofanib resulted in pronounced atrophy of the spermatogenic tubule epithelium. Multinucleated giant cells were observed in the lumen of a part of the tubules. There were no changes in untreated animals. Conclusions: FGFR2 inhibition led to the suppression of spermatogenesis. Male cancer patients should be informed of this potential adverse event before treatment with FGFR2 inhibitors.

Alofanib (RPT835) is a novel allosteric FGFR2 inhibitor with activity in FGFR2-expressing cancers. Here we explore the pharmacokinetic (PK) profile of compound. Five preclinical PK studies were conducted. In Study 1, alofanib was administered to 49 male BALB/C mice via two routes (oral and iv). Mice in group 1 received a single iv injection of the alofanib (30 mg/kg), while mice in group 2 received a single dose (30 mg/kg) via oral gavage. The aim of Study 2 was to evaluate the PK in 24 male Sprague Dawley rats after a single iv dose of 22 mg/kg and oral dosing in capsules at three dose levels (22, 110, and 220 mg/kg). In Study 3, PK of pharmaceutical form of alofanib in male Sprague Dawley rats after a single iv dose of 55.3, 113.8 and 218.7 mg/kg was evaluated. Studies 4 and 5 compared PK profile for alofanib in male Sprague Dawley rats after a single intraduodenal (i.d.) and subcutaneous (s.c.) dosing at 29 and 145 mg/kg. Six animals per dose group were dosed, with plasma samples collected from the tail vein up to 24 hours. Plasma concentrations were quantified by LC-MS/MS using a research qualified method. The PK data are summarized in Table. StudyGroup(dose, mg/kg)C0/Cmax,ng/mlTmax,ht1/2AUC,h*ng/mLCL,mL/min/kgVss,L/kgF,%1iv, 3057739-0.93580386.76.9NCoral/gavage, 3043.61-2NCNANCNCNC2iv, 2279323-0.441423427.10.47-oral/caps, 2222.02.0NC68.0--0.36oral/caps, 11082.32.5NC1.0--0.18oral/caps, 220110.01.0NC1.0--0.183iv, 55.3246499-0.863710523.80.3-iv, 113.8432342-0.7313078814.80.29-iv, 218.7730496-0.6836314510.10.26-4i.d, 29360.5NC116---i.d, 145980.5NC188---5s.c, 2975130.50.9817218---s.c, 145373000.51.7855020--- NC - Parameter cannot be calculated Following oral administration, alofanib appeared rapidly in plasma but could not be detected after 2 hours. Bioavailability for oral administration is estimated to be low ( Citation Format: Ilya Tsimafeyeu, Mikhail Byakhov, Vlatka Bencetić Mihaljević, Jasna Padovan, Genoveva Murillo, Nadezhda Dragun, Evgenia Gavrilova, Sergei Tjulandin. Preclinical pharmacokinetic evaluation of alofanib for cancer treatment [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2017 Oct 26-30; Philadelphia, PA. Philadelphia (PA): AACR; Mol Cancer Ther 2018;17(1 Suppl):Abstract nr B084.

RPT835 (recommended INN, alofanib) is a novel allosteric FGFR2 inhibitor with activity in FGFR2-expressing women's cancers. Administration of RPT835 intravenously (iv) daily demonstrated dramatic effect in ovarian cancer xenografts compared with RPT835 orally daily [S. Tjulandin et al. AACR 2015]. Here we explore the pharmacokinetic (PK) profile of RPT835. Three preclinical PK studies were conducted. In Study 1, RPT835 was administered to 49 male BALB/C mice via two routes (oral and iv). Mice in group 1 received a single iv injection of the RPT835 (30 mg/kg), while mice in group 2 received a single dose of RPT835 (30 mg/kg) via oral gavage. The aim of the Study 2 was to evaluate the PK for RPT835 in 24 male Sprague Dawley rats after a single iv dose of 22 mg/kg and oral dosing in capsules at three dose levels (22, 110 and 220 mg/kg). In Study 3, PK of pharmaceutical form of RPT835 in male Sprague Dawley rats after a single iv dose of 55.3, 113.8 and 218.7 mg/kg was evaluated. Six animals per dose group were dosed, with plasma samples collected from the tail vein up to 24 hours. Plasma concentrations were quantified by LC-MS/MS using a research qualified method. The PK data are summarized in Table. Following oral administration, RPT835 appeared rapidly in plasma (within 30 min), but could not be detected after 2 hours. Bioavailability for oral administration could not be calculated but is estimated to be low ( PK resultsStudyGroup (dose, mg/kg)C0/Cmax, ng/mlTmax, ht1/2AUC, h*ng/mLCL, mL/min/kgVss, L/kgF, %1iv, 3057739-0.93580386.76.9NC - Parameter cannot be calculatedoral/gavage, 3043.61-2NCNCNCNCNC2iv, 2279323-0.441423427.10.47-oral/caps, 2222.02.0NC68.0--0.36oral/caps, 11082.32.5NC1.0--0.18oral/caps, 220110.01.0NC1.0--0.183iv, 55.3246499-0.863710523.80.3-iv, 113.8432342-0.7313078814.80.29-iv, 218.7730496-0.6836314510.10.26- Citation Format: Ilya Tsimafeyeu, Mikhail Byakhov, Vlatka Bencetić Mihaljević, Jasna Padovan, Genoveva Murillo, Sergei Tjulandin. Preclinical pharmacokinetic studies of RPT835, an allosteric FGFR2 inhibitor. [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2015 Nov 5-9; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2015;14(12 Suppl 2):Abstract nr B146.

Purpose To evaluate the addition of paclitaxel to an anthracycline-based adjuvant regimen and to compare this combination with the same regimen given as primary systemic (neoadjuvant) therapy. Patients and Methods A total of 1,355 women with operable breast cancer were randomly assigned to one of three treatments: surgery followed by adjuvant doxorubicin (75 mg/m2) followed by cyclophosphamide, methotrexate, and fluorouracil (CMF; arm A); surgery followed by adjuvant paclitaxel (200 mg/m2) plus doxorubicin (60 mg/m2), followed by CMF (arm B); or paclitaxel (200 mg/m2) plus doxorubicin (60 mg/m2) followed by CMF followed by surgery (arm C). The two coprimary objectives were to assess the effects on relapse-free survival (RFS) of the addition of paclitaxel to postoperative chemotherapy (arm B v arm A) and primary chemotherapy versus adjuvant chemotherapy (arm B v arm C). Results Doxorubicin plus paclitaxel followed by CMF was well-tolerated as adjuvant or as primary chemotherapy. The addition of paclitaxel to adjuvant doxorubicin followed by CMF significantly improved RFS compared with adjuvant doxorubicin alone followed by CMF (hazard ratio [HR], 0.73; P = .03). Distant RFS was similarly improved (HR, 0.70; P = .027). There was no significant difference in RFS when the paclitaxel/doxorubicin/CMF chemotherapy was given before surgery compared with the same regimen given after surgery (HR, 1.21; P = .18). However, the rate of breast-conserving surgery was significantly higher with preoperative chemotherapy (63% v 34%; P < .001). Conclusion Incorporating paclitaxel into anthracycline-based adjuvant therapy resulted in a significant improvement in RFS and distant RFS. When given as primary systemic therapy, the paclitaxel-containing regimen allowed breast-sparing surgery in a significant percentage of patients.

Alofanib (formerly known as RPT835) is a novel allosteric FGFR2 inhibitor with activity in FGFR2-expressing triple-negative breast cancer [Tjulandin S, et al. San Antonio Breast Cancer Symposium 2014]. Early data suggest that combining FGFR2 inhibitors with platinum-containing cytotoxic agents for the treatment of epithelial ovarian cancer may yield increased antitumor activity [Cole C, et al. Cancer Biol Ther. 2010]. We investigated antitumor activity of alofanib in ovarian cancer in vitro and in vivo. To assess the efficacy of alofanib on FGF-mediated cell proliferation, ovarian cancer (SKOV-3) FGFR2-expressing cells were incubated in a 96-well microculture plate and were treated with serially diluted RPT835. Basic FGF was added at a concentration of 25 ng/ml. Control wells were left untreated. Cell growth inhibition was determined using Promega's Cell Titer-Glo® assay. Immunocompromised mice were used for xenotransplantation of FGFR2 high-expressing ovarian cancer cells (SCOV-3). Seventy animals with measurable tumors were selected on day 10 and randomized into control groups (no treatment or chemotherapy alone (paclitaxel + carboplatin) and treatment groups (alofanib orally or intravenously (different dose levels) in combination with chemotherapy). Measurements of tumor volume (mm3) were performed by digital calipers every 3 days during 30 days after tumor inoculation. Basic FGF significantly increased proliferation of the ovarian cancer cells in untreated control group (P = 0.001). Alofanib treatment resulted in growth inhibition of SKOV-3 cell line in vitro. Treatment of alofanib in combination with paclitaxel/carboplatin demonstrated significant tumor growth delay phenotype in all treatment groups compared to control non-treatment groups. Alofanib exhibited a dose-dependent effect on tumor growth. Daily intravenous regimen of alofanib (total maximum dose per week was 350 mg/kg) demonstrated dramatic effect (inhibiting growth by 80% and by 53% in comparison with vehicle and chemotherapy group alone, respectively (P These results provide strong rationale for evaluation of alofanib in combination with paclitaxel and carboplatin in patients with ovarian cancer. Citation Format: Sergei Tjulandin, Mikhail Byakhov, Evgenia Stepanova, Dmitry Khochenkov, Daniel Harrison, Ilya Tsimafeyeu. Alofanib, a novel allosteric FGFR2 inhibitor, shows potent antitumor activity in ovarian cancer with FGFR2 expression. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 796. doi:10.1158/1538-7445.AM2015-796

Purpose: The European Cooperative Trial in Operable breast cancer (ECTO) randomly tested whether efficacy of adjuvant doxorubicin followed by i.v. cyclophosphamide, methotrexate, and fluorouracil (CMF; doxorubicin → CMF, arm A) could be improved by adding paclitaxel (doxorubicin/paclitaxel → CMF) as adjuvant (arm B) or primary systemic therapy (PST, arm C). We report here feasibility, tolerability, locoregional antitumor activity, and breast conservation rate. Methods: A total of 1,355 women entered the study. Feasibility and safety were compared in arm A versus arms B plus C. Surgical findings were compared in arms A plus B versus arm C. Results: Grade 3 or 4 National Cancer Institute toxicities were low ( Conclusions: Doxorubicin/paclitaxel → CMF is feasible, safe, and well tolerated. Given as PST, it is markedly active, allowing for breast-sparing surgery in a large fraction of patients.

537 Background: At the time the ECTO was designed in 1996, taxanes were only indicated for patients with metastatic breast cancer. However, paclitaxel and docetaxel were still to be tested in the adjuvant setting. In addition there was relatively scarce information on the comparative efficacy of neoadjuvant and adjuvant regimens. The ECTO trial was designed to evaluate the addition of paclitaxel to an anthracycline-based adjuvant regimen and to compare this combination with the same regimen given as primary systemic (neoadjuvant) therapy. Methods: A total of 1,355 women with operable breast cancer were randomized to one of three treatments: 1) surgery followed by adjuvant single agent doxorubicin (A) followed by CMF (arm A); 2) surgery followed by adjuvant paclitaxel plus doxorubicin (AT) followed by CMF (arm B); 3) AT followed by CMF followed by surgery (arm C). The two co-primary objectives were to assess the effects on freedom from progression (FFP) of: 1) the addition of paclitaxel to post-operative chemotherapy (arm B versus arm A); and 2) primary versus adjuvant chemotherapy (arm B versus arm C). Results: At 10 years, in the adjuvant setting FFP remained statistically significant in favor of AT followed by CMF (arm B, HR 0.77, P=0.045). Distant FFP was similarly improved but overall survival was not (HR 0.82, P=0.24). There was no significant difference in FFP when chemotherapy was given after surgery compared with the same regimen given before surgery (arm B vs arm C, HR 0.79, P=0.07). In the primary chemotherapy arm, patients who achieved a pathological complete remission (pCR) had improved distant FFP (P < 0.001) compared to patients who did not achieve pCR. When given as primary systemic therapy, the paclitaxel-containing regimen allowed breast-sparing surgery in a significant percentage of patients, which did not translate in an increased risk of ipsilateral breast recurrence compared to the risk observed in patients in the adjuvant arms. Conclusions: Incorporating paclitaxel into anthracycline-based adjuvant therapy resulted in a significantly improved FFP and DFFP.

503 Background: The monoclonal antibody trastuzumab (H) has been shown to improve event-free survival (EFS) and pathologic complete response (pCR) in patients with HER2-positive locally advanced or inflammatory breast cancer receiving neoadjuvant chemotherapy with or without one year of trastuzumab in the primary analysis of the NOAH study (Gianni L, Lancet 2010). Updated EFS and overall survival (OS) results are now presented. Methods: In this international, multicenter, open-label, randomized phase III trial patients with locally advanced or inflammatory breast cancer were randomized 1:1 to receive CT+H followed by adjuvant H versus CT alone. A parallel cohort of 99 comparable patients with HER2-negative disease was included and treated with the same chemotherapy regimen. The neoadjuvant chemotherapy regimen included doxorubicin, paclitaxel, cyclophosphamide, methotrexate and 5-fluorouracil. The primary objective was to compare EFS defined as time from randomization to disease recurrence or progression [local, regional, distant or contralateral] or death due to any cause). Results: After a median follow up of 5.4 years, the EFS benefit with trastuzumab was confirmed. Cardiac tolerability was good despite concurrent administration of trastuzumab with doxorubicin. Two patients (2%) developed reversible symptomatic congestive heart failure and are presently alive. Conclusions: Present analysis confirms the significant EFS benefit observed in the primary analysis of the NOAH study, and shows a strong trend towards improved OS with the addition of trastuzumab to chemotherapy. pCR rate may be considered as a possible primary endpoint and early indicator of benefit in future neoadjuvant studies of HER2-targeted agents. Clinical trial information: 86043495. [Table: see text]