Plain language summary of the FOENIX-CCA2 study: futibatinib for people with advanced bile duct cancer.

WHAT IS THIS SUMMARY ABOUT?: This summary describes the results from a phase 2 study called FOENIXCCA2. The study evaluated treatment with futibatinib in people with a rare form of advanced bile duct cancer called intrahepatic cholangiocarcinoma (or iCCA), where the tumors have changes in the structure of a gene called FGFR2. These changes include FGFR2 gene fusions. Bile duct cancer often returns after surgery or cannot be treated by surgery because the tumor has spread, so it requires treatment with chemotherapy. People live for a median of 1 year after their first chemotherapy treatment and 6 months after their second treatment. This study included people whose cancer had grown/spread after one or more chemotherapy treatments. The aims of the study were to see if futibatinib could shrink the size of tumors and stop the cancer from growing/spreading and to see how long people lived when treated with futibatinib. Clinicians also looked at side effects from taking futibatinib and at how it affected people's quality of life. WHAT WERE THE RESULTS?: Futibatinib treatment shrank tumors in over 80% of people who received treatment. Tumors shrank by at least 30% in 42% of people. Futibatinib stopped tumors from growing/spreading for a median of 9.7 months. People who took the medicine lived for a median of 21.7 months, and 72% of people were still alive after 1 year. Side effects from taking futibatinib were like those reported for similar medicines, and clinicians considered the side effects to be manageable by adjusting the dose of futibatinib or treating the side effects. Most people reported that their quality of life stayed the same or improved during the first 9 months of taking futibatinib. WHAT DO THE RESULTS MEAN?: The results support the use of futibatinib for treating people with advanced bile duct cancer. Based on the results of this study, futibatinib is now approved in the US, Europe, and Japan. Futibatinib is approved for treating adults with advanced bile duct cancer who have received previous treatment for their cancer, and whose tumors have a gene fusion or other change in the FGFR2 gene.Clinical Trial Registration: NCT02052778 (FOENIX-CCA2).

Convergent MAPK pathway alterations mediate acquired resistance to FGFR inhibitors in FGFR2 fusion-positive cholangiocarcinoma.

BACKGROUND & AIMS: There is a knowledge gap in understanding mechanisms of resistance to fibroblast growth factor receptor (FGFR) inhibitors (FGFRi) and a need for novel therapeutic strategies to overcome it. We investigated mechanisms of acquired resistance to FGFRi in patients with FGFR2-fusion-positive cholangiocarcinoma (CCA). METHODS: A retrospective analysis of patients who received FGFRi therapy and underwent tumor and/or cell-free DNA analysis, before and after treatment, was performed. Longitudinal circulating tumor DNA samples from a cohort of patients in the phase I trial of futibatinib (NCT02052778) were assessed. FGFR2-BICC1 fusion cell lines were developed and secondary acquired resistance mutations in the mitogen-activated protein kinase (MAPK) pathway were introduced to assess their effect on sensitivity to FGFRi in vitro. RESULTS: On retrospective analysis of 17 patients with repeat sequencing following FGFRi treatment, new FGFR2 mutations were detected in 11 (64.7%) and new alterations in MAPK pathway genes in nine (52.9%) patients, with seven (41.2%) patients developing new alterations in both the FGFR2 and MAPK pathways. In serially collected plasma samples, a patient treated with an irreversible FGFRi tested positive for previously undetected BRAF V600E, NRAS Q61K, NRAS G12C, NRAS G13D and KRAS G12K mutations upon progression. Introduction of a FGFR2-BICC1 fusion into biliary tract cells in vitro sensitized the cells to FGFRi, while concomitant KRAS G12D or BRAF V600E conferred resistance. MEK inhibition was synergistic with FGFRi in vitro. In an in vivo animal model, the combination had antitumor activity in FGFR2 fusions but was not able to overcome KRAS-mediated FGFRi resistance. CONCLUSIONS: These findings suggest convergent genomic evolution in the MAPK pathway may be a potential mechanism of acquired resistance to FGFRi. CLINICAL TRIAL NUMBER: NCT02052778. IMPACT AND IMPLICATIONS: We evaluated tumors and plasma from patients who previously received inhibitors of fibroblast growth factor receptor (FGFR), an important receptor that plays a role in cancer cell growth, especially in tumors with abnormalities in this gene, such as FGFR fusions, where the FGFR gene is fused to another gene, leading to activation of cancer cell growth. We found that patients treated with FGFR inhibitors may develop mutations in other genes such as KRAS, and this can confer resistance to FGFR inhibitors. These findings have several implications for patients with FGFR2 fusion-positive tumors and provide mechanistic insight into emerging MAPK pathway alterations which may serve as a therapeutic vulnerability in the setting of acquired resistance to FGFRi.

Futibatinib for FGFR2-Rearranged Intrahepatic Cholangiocarcinoma.

BACKGROUND: Alterations in fibroblast growth factor receptor 2 (FGFR2) have emerged as promising drug targets for intrahepatic cholangiocarcinoma, a rare cancer with a poor prognosis. Futibatinib, a next-generation, covalently binding FGFR1-4 inhibitor, has been shown to have both antitumor activity in patients with FGFR-altered tumors and strong preclinical activity against acquired resistance mutations associated with ATP-competitive FGFR inhibitors. METHODS: In this multinational, open-label, single-group, phase 2 study, we enrolled patients with unresectable or metastatic FGFR2 fusion-positive or FGFR2 rearrangement-positive intrahepatic cholangiocarcinoma and disease progression after one or more previous lines of systemic therapy (excluding FGFR inhibitors). The patients received oral futibatinib at a dose of 20 mg once daily in a continuous regimen. The primary end point was objective response (partial or complete response), as assessed by independent central review. Secondary end points included the response duration, progression-free and overall survival, safety, and patient-reported outcomes. RESULTS: Between April 16, 2018, and November 29, 2019, a total of 103 patients were enrolled and received futibatinib. A total of 43 of 103 patients (42%; 95% confidence interval, 32 to 52) had a response, and the median duration of response was 9.7 months. Responses were consistent across patient subgroups, including patients with heavily pretreated disease, older adults, and patients who had co-occurring TP53 mutations. At a median follow-up of 17.1 months, the median progression-free survival was 9.0 months and overall survival was 21.7 months. Common treatment-related grade 3 adverse events were hyperphosphatemia (in 30% of the patients), an increased aspartate aminotransferase level (in 7%), stomatitis (in 6%), and fatigue (in 6%). Treatment-related adverse events led to permanent discontinuation of futibatinib in 2% of the patients. No treatment-related deaths occurred. Quality of life was maintained throughout treatment. CONCLUSIONS: In previously treated patients with FGFR2 fusion or rearrangement-positive intrahepatic cholangiocarcinoma, the use of futibatinib, a covalent FGFR inhibitor, led to measurable clinical benefit. (Funded by Taiho Oncology and Taiho Pharmaceutical; FOENIX-CCA2 ClinicalTrials.gov number, NCT02052778.).

A phase II study of TAS-117 in patients with advanced solid tumors harboring germline PTEN-inactivating mutations.

PTEN acts as a potent tumor suppressor within the PI3K/AKT/mTOR pathway. Germline mutations in the PTEN gene are a hallmark of PTEN hamartoma tumor syndrome, which includes Cowden syndrome, where they appear to elevate lifetime risk of cancer. Targeted AKT directed therapy has been proposed as an effective approach in cancer patients having germline PTEN mutations. The mechanism of action, safety and dosing regimen for the novel allosteric AKT inhibitor TAS-117 have been explored in a phase I study in Japan in which activity was observed against certain tumor types. Here we describe the study protocol of an international, two-part phase II study evaluating the safety, tolerability, pharmacokinetics, pharmacodynamics and antitumor activity of TAS-117 in patients with advanced solid tumors harboring germline PTEN-inactivating mutations.

Signaling paths control growth and activities inside cells. Overactivity in these paths can encourage many types of cancers to develop. Tumor suppressor proteins can inhibit cell signals that promote cancer. This protection can be lost if there are errors in any gene coding for a tumor suppressor protein. We are carrying out a clinical study to test TAS-117, a potential new oral medicine, in people who have solid tumors and whose cells have changes in their genes that inactivate a tumor suppressor protein called PTEN. TAS-117 targets part of a signaling path that may be overactive due to loss of PTEN activity. In early research, TAS-117 has shown promising activity against certain tumor types. Our trial will explore if TAS-117 can provide a new treatment for rare forms of cancer where genetic changes have led to a loss of PTEN activity. Clinical Trial Registration: NCT04770246 (ClinicalTrials.gov).

Glembatumumab vedotin for patients with metastatic, gpNMB overexpressing, triple-negative breast cancer ("METRIC"): a randomized multicenter study.

The METRIC study (NCT#0199733) explored a novel antibody-drug conjugate, glembatumumab vedotin (GV), targeting gpNMB that is overexpressed in ~40% of patients with triple-negative breast cancer (TNBC) and associated with poor prognosis. The study was a randomized, open-label, phase 2b study that evaluated progression-free survival (PFS) of GV compared with capecitabine in gpNMB-overexpressing TNBC. Patients who had previously received anthracycline and taxane-based therapy were randomized 2:1 to receive, GV (1.88 mg/kg IV q21 days) or capecitabine (2500 mg/m2 PO daily d1-14 q21 days). The primary endpoint was RECIST 1.1 PFS per independent, blinded central review. In all, 327 patients were randomized to GV (213 treated) or capecitabine (92 treated). Median PFS was 2.9 months for GV vs. 2.8 months for capecitabine. The most common grade ≥3 toxicities for GV were neutropenia, rash, and leukopenia, and for capecitabine were fatigue, diarrhea, and palmar-plantar erythrodysesthesia. The study did not meet the primary endpoint of improved PFS over capecitabine or demonstrate a relative risk/benefit improvement over capecitabine.

The biggest challenges currently facing companion diagnostic advancement.

Low productivity in the pharmaceutical industry positions personalized medicine and companion diagnostics as an attractive approach. The oncology community is enthusiastic and optimistic that advances in molecular diagnostics have the potential to materialize the dream of personalized cancer therapy with the aim to: help the drug industry enhance the probability of success and, probably, accelerate time to market; help the diagnostics industry develop diagnostic tests utilizing precious human samples; and support accurate diagnosis and selection of the most efficacious and least toxic therapies. However, this spectacular road is not yet paved and remains facing the following biggest challenges: the need for better understanding of biology and limitations of preclinical models; pre-analytical variables that are likely to alter results; analytical discrepancies; and the wide gap between clinical/pharmaceutical and diagnostic understandings. This article explores these challenges, their possible impacts, and provides some suggestions for mitigation.

Phase I study of U3-1287, a fully human anti-HER3 monoclonal antibody, in patients with advanced solid tumors.

PURPOSE: HER3 is a key dimerization partner for other HER family members, and its expression is associated with poor prognosis. This first-in-human study of U3-1287 (NCT00730470), a fully human anti-HER3 monoclonal antibody, evaluated its safety, tolerability, and pharmacokinetics in patients with advanced solid tumor. EXPERIMENTAL DESIGN: The study was conducted in 2 parts: part 1--sequential cohorts received escalating doses (0.3-20 mg/kg) of U3-1287 every 2 weeks, starting 3 weeks after the first dose; part 2--additional patients received 9, 14, or 20 mg/kg U3-1287 every 2 weeks, based on observed tolerability and pharmacokinetics from part 1. Recommended phase II dose, adverse event rates, pharmacokinetics, and tumor response were determined. RESULTS: Fifty-seven patients (part 1: 26; part 2: 31) received U3-1287. As no dose-limiting toxicities were reported, the maximum-tolerated dose was not reached. The maximum-administered dose was 20 mg/kg every 2 weeks. The most frequent adverse events related to U3-1287 were fatigue (21.1%), diarrhea (12.3%), nausea (10.5%), decreased appetite (7.0%), and dysgeusia (5.3%). No patient developed anti-U3-1287 antibodies. In these heavily pretreated patients, stable disease was maintained 9 weeks or more in 19.2% in part 1 and 10 weeks or more in 25.8% in part 2. CONCLUSION: U3-1287 treatment was well tolerated, and some evidence of disease stabilization was observed. Pharmacokinetic data support U3-1287 dosing of 9 to 20 mg/kg every 2 to 3 weeks. Combination studies of U3-1287 are ongoing.

A phase 2 multicenter study of tivantinib (ARQ 197) monotherapy in patients with relapsed or refractory germ cell tumors.

BACKGROUND: Tivantinib is a selective, small-molecule inhibitor of the MET receptor tyrosine kinase. Preclinical and phase 1 data suggested a possible role for MET in the pathophysiology of germ cell tumors (GCTs) and a potential clinical benefit from tivantinib in patients with these tumors. METHODS: Men (≥ 16 years) with relapsed or refractory, histologically confirmed, non-central nervous system GCTs received oral tivantinib 360 mg twice daily in 28-day cycles until progressive disease or unacceptable toxicity. The primary endpoint was objective response rate in the first 4 cycles, with study termination for <2 responses among the first 21 patients. Secondary endpoints included 12-week progression-free survival (PFS), overall survival (OS), and safety. RESULTS: Twenty-seven patients were enrolled in 9 months (median age, 32 years). Most patients had tumors with nonseminoma histology (n = 25), and primary tumor sites were testis (n = 24) and mediastinum (n = 3). Among 25 evaluable patients, no objective responses were observed; accrual was halted when the 21st patient became evaluable. Best response was stable disease (n = 5). Median PFS was 1 month, the 12-week PFS rate was 21 %, and median OS was 6 months. Grade 3 or 4 adverse events considered related to study drug included grade 3 pneumonia and grade 3 syncope (n = 1, each). CONCLUSIONS: Tivantinib was well tolerated but did not demonstrate single-agent activity in patients with relapsed/refractory GCTs. Rapid accrual to this phase 2 trial was achieved in this rare patient population through multicenter collaboration.

A phase 1 study of efatutazone, an oral peroxisome proliferator-activated receptor gamma agonist, administered to patients with advanced malignancies.

BACKGROUND: Efatutazone (CS-7017), a novel peroxisome proliferator-activated receptor gamma (PPARγ) agonist, exerts anticancer activity in preclinical models. The authors conducted a phase 1 study to determine the recommended phase 2 dose, safety, tolerability, and pharmacokinetics of efatutazone. METHODS: Patients with advanced solid malignancies and no curative therapeutic options were enrolled to receive a given dose of efatutazone, administered orally (PO) twice daily for 6 weeks, in a 3 + 3 intercohort dose-escalation trial. After the third patient, patients with diabetes mellitus were excluded. Efatutazone dosing continued until disease progression or unacceptable toxicity, with measurement of efatutazone pharmacokinetics and plasma adiponectin levels. RESULTS: Thirty-one patients received efatutazone at doses ranging from 0.10 to 1.15 mg PO twice daily. Dose escalation stopped when maximal impact on PPARγ-related biomarkers had been reached before any protocol-defined maximum-tolerated dose level. On the basis of a population pharmacokinetic/pharmacodynamic analysis, the recommended phase 2 dose was 0.5 mg PO twice daily. A majority of patients experienced peripheral edema (53.3%), often requiring diuretics. Three episodes of dose-limiting toxicities, related to fluid retention, were noted in the 0.10-, 0.25-, and 1.15-mg cohorts. Of 31 treated patients, 27 were evaluable for response. A sustained partial response (PR; 690 days on therapy) was observed in a patient with myxoid liposarcoma. Ten additional patients had stable disease (SD) for ≥60 days. Exposures were approximately dose proportional, and adiponectin levels increased after 4 weeks of treatment at all dose levels. Immunohistochemistry of archived specimens demonstrated that PPARγ and retinoid X receptor expression levels were significantly greater in patients with SD for ≥60 days or PR (P = .0079), suggesting a predictive biomarker. CONCLUSIONS: Efatutazone demonstrates acceptable tolerability with evidence of disease control in patients with advanced malignancies.