Combining CD40 agonist mitazalimab with mFOLFIRINOX in previously untreated metastatic pancreatic ductal adenocarcinoma (OPTIMIZE-1): a single-arm, multicentre phase 1b/2 study.

BACKGROUND: Current systemic therapies for metastatic pancreatic ductal adenocarcinoma are associated with poor outcomes with a 5-year overall survival rate under 5%. We aimed to assess the safety and antitumour activity of mitazalimab, a human CD40 agonistic IgG1 antibody, with modified FOLFIRINOX (mFOLFIRINOX; fluorouracil, leucovorin, oxaliplatin, and irinotecan), in chemotherapy-naive patients with metastatic pancreatic ductal adenocarcinoma. METHODS: OPTIMIZE-1 was a single-arm, multicentre, phase 1b/2 study which enrolled adults with histologically-confirmed metastatic pancreatic ductal adenocarcinoma and European Cooperative Oncology Group performance status 0 or 1 in 14 university hospitals in Belgium, France, and Spain. The primary endpoint of phase 1b was to determine the recommended phase 2 dose of intravenous mitazalimab (450 µg/kg or 900 µg/kg) when combined with intravenous mFOLFIRINOX (oxaliplatin 85 mg/m2, leucovorin 400 mg/m2, irinotecan 150 mg/m2, fluorouracil 2400 mg/m2). In the first 21-day treatment cycle, mitazalimab was administered on days 1 and 10, and mFOLFIRINOX on day 8. In subsequent 14-day cycles mitazalimab was administered 2 days after mFOLFIRINOX. The phase 2 primary endpoint was objective response rate. Activity and safety analyses were conducted on the full analysis set (all patients who received the combination of mitazalimab at the recommended phase 2 dose and mFOLFIRINOX for at least two treatment cycles) and safety set (all patients who received any study treatment), respectively. Enrolment is complete, and data represents a primary analysis of the ongoing trial. The trial is registered at Clinicaltrials.gov (NCT04888312). FINDINGS: Between Sept 29, 2021, and March 28, 2023, 88 patients were screened and 70 patients were enrolled (40 [57%] were female and 30 [43%] were male). In phase 1b, 900 µg/kg mitazalimab was determined as the recommended phase 2 dose. Overall, five patients received 450 µg/kg mitazalimab; 65 received 900 µg/kg mitazalimab. No dose-limiting toxicities were observed at 450 µg/kg, and one dose-limiting toxicity was observed at 900 µg/kg. 57 patients were evaluated for activity, and all 70 patients were included in the safety set. At data cutoff on Nov 14, 2023, median follow-up was 12·7 months (95% CI 11·1-15·7). Of the 57 patients, 29 (51%) remained on study and 18 (32%) remained on treatment. The primary endpoint (objective response rate >30%) was met (objective response rates in 23 [40%]; one-sided 90% CI ≥32 of 57 patients). The most common grade 3 or worse adverse events were neutropenia (18 [26%] of 70 patients), hypokalaemia (11 patients [16%]), and anaemia and thrombocytopenia (eight patients [11%]). Serious adverse events were reported in 29 (41%) of 70 patients, the most common being vomiting (five [7%] of 70 patients), decreased appetite (four [6%]), and diarrhoea and cholangitis (three [4%] of 70 patients for each), none considered related to mitazalimab. No treatment-related deaths were reported. INTERPRETATION: Mitazalimab with mFOLFIRINOX demonstrated manageable safety and encouraging activity, warranting continued development in a phase 3, randomised, controlled trial. The results from OPTIMIZE-1 pave the way for further exploration and confirmation of a novel immunotherapy treatment regimen for metastatic pancreatic ductal adenocarcinoma, which is a complex and aggressive cancer with very low survival rates and restricted treatment options. FUNDING: Alligator Bioscience.

Prognostic factors for survival with nab-paclitaxel plus gemcitabine in metastatic pancreatic cancer in real-life practice: the ANICE-PaC study.

BACKGROUND: Treatment with nab-paclitaxel plus gemcitabine increases survival in patients with metastatic pancreatic cancer. However, the assessment of treatment efficacy and safety in non-selected patients in a real-life setting may provide useful information to support decision-making processes in routine practice. METHODS: Retrospective, multicenter study including patients with metastatic pancreatic cancer, who started first-line treatment with nab-paclitaxel plus gemcitabine between December 2013 and June 2015 according to routine clinical practice. In addition to describing the treatment pattern, overall survival (OS) and progression-free survival (PFS) were assessed for the total sample and the exploratory subgroups based on the treatment and patients' clinical characteristics. RESULTS: All 210 eligible patients had a median age of 65.0 years (range 37-81). Metastatic pancreatic adenocarcinoma was recurrent in 46 (21.9%) patients and de novo in 164 (78.1%); 38 (18%) patients had a biliary stent. At baseline, 33 (18.1%) patients had an ECOG performance status ≥2. Patients received a median of four cycles of treatment (range 1-21), with a median duration of 3.5 months; 137 (65.2%) patients had a dose reduction of nab-paclitaxel and/or gemcitabine during treatment, and 33 (17.2%) discontinued treatment due to toxicity. Relative dose intensity (RDI) for nab-paclitaxel, gemcitabine, and the combined treatment was 66.7%. Median OS was 7.2 months (95% CI 6.0-8.5), and median PFS was 5.0 months (95% CI 4.3-5.9); 50 patients achieved either a partial or complete response (ORR 24.6%). OS was influenced by baseline ECOG PS, NLR and CA 19.9, but not by age ≥ 70 years and/or the presence of hepatobiliary stent or RDI < 85%. All included variables, computed as dichotomous, showed a significant contribution to the Cox regression model to build a nomogram for predicting survival in these patients: baseline ECOG 0-1 vs. 2-3 (p = 0.030), baseline NLR > 3 vs. ≤ 3 (p = 0.043), and baseline CA 19.9 > 37 U/mL vs. ≤37 U/mL (p = 0.004). CONCLUSIONS: Nab-Paclitaxel plus gemcitabine remain effective in a real-life setting, despite the high burden of dose reductions and poorer performance of these patients. A nomogram to predict survival using baseline ECOG performance status, NLR and CA 19.9 is proposed.

Skull metastasis from rectal gastrointestinal stromal tumours.

Gastrointestinal stromal tumours (GIST) are the most common mesenchymal neoplasm of the gastrointestinal tract. Rectum localisation is infrequent for these neoplasms, accounting for about 5% of all cases. Distant metastases of GIST are also rare. We present a patient with special features: the tumour is localised in rectum and it has an uncommon metastatic site, the skull, implying a complex differential diagnosis approach.