• The natural history of fibroblast growth factor receptor (FGFR)-altered cholangiocarcinoma (CCA)

      Goyal, L.; Lamarca, Angela; Strickler, J. H.; Cecchini, M.; Ahn, D. H.; Baiev, I.; Boileve, A.; Tazdait, M.; Hannan, L. M.; Jia, J. Q.; et al. (2020)
      Background: Genetic alterations in the FGFR pathway are emerging as promising therapeutic targets in CCA. The clinical and molecular features of patients (pts) with CCA harboring FGFR genetic alterations are reported here. Methods: A retrospective chart review was performed in pts with CCA who were found to have an FGFR alteration on tumor molecular profiling as part of routine care between 9/2007 and 12/2019. Data on demographics, risk factors, pathology, molecular characteristics, systemic therapies, radiographical response, time on treatment, and overall survival (OS) were collected in a multi-center collaborative effort across seven academic centers. Results: Among 135 pts with FGFR-altered CCA, the median age at diagnosis was 57 years old (range = 25-92 years), and 80 (59.3%) pts were female, 129 (95.6%) had intrahepatic CCA, and 6 (5.6%) had chronic HBV. At presentation, 28.2% of pts had resectable disease, including 65.0% with Stage I-II, 22.5% with Stage III, and 5.0% with Stage IV. At the time of initial diagnosis, CA19-9 was < 35U/mL in 42.6% of pts. Bone metastases were observed in 41 (30.6%) pts with advanced disease. FGFR2 fusions were the most common FGFR alteration (68.2%), followed by FGFR2 mutations (21.5%), FGFR3 mutations (3.7%), FGFR2 rearrangements (1.5%), FGFR1 amplification (1.5%), and FGFR2 amplification (1.5%). The most common FGFR2 fusion partners were BICC1 (28.3%), SORBS1 (4.4%), POC1B (3.3%), and TACC2 (3.3%). The median lines of palliative systemic therapies received was 3 (range = 0-8), and 40/135 (29.6%) pts received a liver-directed therapy. For the 55 (59.8%) pts with FGFR2 fusions who received gemcitabine/cisplatin as first-line palliative systemic therapy, the median time on treatment was 6.2 months (95% CI: 4.1-9.3). The median OS from time of initial diagnosis was 36.1 months (95% CI: 28.3-51.6) in the FGFR2 fusion positive cohort. Among the 92 pts with FGFR2 fusions, 70 (76.1%) pts received an FGFR inhibitor on a clinical trial; 12 (17.1%) were subsequently treated with a second FGFR inhibitor, and 58.3% stayed on the second FGFR inhibitor for ≥4 months. Pts with a BICC1 fusion partner (n = 16) had an overall response rate of 42.9% on FGFR-selective inhibitors compared to 30.8% in non-BICC1 fusion partners (n = 54). Conclusions: Pts with CCA harboring FGFR alterations were found to have a high rate of normal CA19-9, high rate of bone metastases, and short median time on treatment on first-line palliative gemcitabine/cisplatin. Additional comparative studies are necessary to evaluate these findings.
    • PROCLAIM-CX-072: Analysis of patients with advanced solid tumors receiving long-term treatment with CX-072, a PD-L1 probody therapeutic, as a single agent or in combination with ipilimumab

      Thistlethwaite, Fiona C; Naing, A.; Gil-Martin, M.; LoRusso, P.; Randhawa, M.; Eskens, F.; Sanborn, R. E.; Uboha, N. V.; Cho, D. C.; Spira, A. I.; et al. (2020)
      Background: Monotherapy with immune checkpoint inhibitors (ICIs) has demonstrated efficacy in many cancers. Combining ICIs PD-L1 + CTLA-4 enhanced efficacy but worsened toxicity vs monotherapy; therefore, CTLA-4 dose modifications are often needed, despite a dose-response effect having been shown for efficacy. CX-072 is an investigational PD-L1 PROBODY therapeutic that is preferentially activated in the tumor microenvironment (TME); localized activation may reduce immune-related AEs (irAEs). PROCLAIM-CX-072-001 identified 10 mg/kg Q2W (Mono10) as the recommended monotherapy dose. Here we provide data for Mono10 and for dose escalation of CX-072 in combination with IPI (Combo), with a focus on long-term (?6 mo) therapy. Methods: Mono10 was evaluated in multiple tumor types. Combo doses evaluated were CX-072 0.3–10 mg/kg and IPI 3–10 mg/kg Q3W. Patients (pts) with ?6 mo treatment duration (?6M-TD) were compared to those with < 6 mo of treatment ( < 6M-TD) as of November 30, 2019. Results: Disease control rates (DCR = CR+PR+SD) were 41% for Mono10 (n = 47 of 114; 10 PRs) and 37% for Combo (n = 10 of 27; 1CR + 4 PRs (1CR and 3PRs at 3 mg/kg IPI [IPI3]). Additional results are shown in the table. No treatment-related adverse events (TRAEs) led to death. The most common reason for discontinuation (dc) in all groups was disease progression. Conclusions: CX-072 monotherapy demonstrated durable responses consistent with activation of the PROBODY therapeutic in the TME. The safety profile supports the tolerability of CX-072 as monotherapy and when combined with IPI3. CX-072 + IPI3 demonstrated activity in heavily pretreated pts with various tumors. The safety profile of the combination of CX-072 with IPI3 compares favorably to historical data (grade ?3 TRAEs 55% and leading to dc in 36%; Larkin J, et al. N Engl J Med. 2015;373:23-34). CX-072 + IPI3 is being explored in a phase 2 study in 2L melanoma