Belanger, Bruce

Abstract BACKGROUND: nal-IRI is a liposomal formulation of irinotecan (topoisomerase-1 inhibitor). Preclinical data show that nal-IRI accumulates in BMs and prolongs survival in animal models of BM. Findings from a phase 1 expansion study (NCT01770353), evaluating patients with mBC and active BM, are reported. METHODS: This phase 1 expansion study enrolled patients with mBC who received multiple prior lines of cytotoxic therapy in the metastatic setting, including one cohort with mBC and active BM, defined as radiographic evidence of new or progressive central nervous system (CNS) metastases after radiation therapy with ≥1 lesion of ≥1 cm in the longest dimension on gadolinium-enhanced magnetic resonance imaging. Patients received nal-IRI 50 mg/m2 (free-base equivalent; FBE) every two weeks (q2w) as an intravenous infusion over 90 minutes, escalating to 70 mg/m2 FBE q2w, if tolerated. RECIST v1.1 and modified RECIST criteria were used to assses non-CNS and CNS disease, respectively. RESULTS: In total, 30 patients were enrolled (10 with active BM). Median age was 53 years (range 29–70 years) and median number of prior cytotoxic anti-cancer regimens was 3 (range 0–6); 29 patients received ≥1 dose of nal-IRI 50 mg/m2 FBE. Overall, nal-IRI monotherapy appeared to be well tolerated, and achieved ≥30% objective response rates for both CNS and non-CNS disease. Among the 10 patients with active BM, 6 achieved CNS disease control (3 partial responses [PRs] and 3 stable disease [SD]), including one patient with durable CNS SD and non-CNS PR for 2 years. Among 7 patients with serial evaluation of CNS metastases posttreatment, 6 patients achieved a reduction in target CNS lesions compared with baseline. CONCLUSION: Treatment with nal-IRI resulted in CNS disease control among 6 of 10 heavily pretreated patients with mBC and active BM. Further exploration of nal-IRI in patients with mBC and active BM is warranted.

Abstract Background nal-IRI is a liposomal formulation of irinotecan (topoisomerase-1 inhibitor), using intraliposomal stabilisation technology to enable high drug load and in-vivo stability. The expansion of Phase I NCT01770353 evaluated nal-IRI in patients (pts) with mBC. Methods This Phase I expansion study enrolled mBC pts (Cohort 1: ER+ and/or PR+ HER2 BC (C-1); Cohort 2: Triple Negative BC (TNBC, C-2); Cohort 3: BC with active Brain Metastasis (C-3)). Key inclusion criteria: ECOG ≤1; adequate organ function; received >1 to ≤5 prior lines of cytotoxic therapy in metastatic setting, except TNBC pts who could have progressed within 12 months of adjuvant therapy. Pts received nal-IRI 50 mg/m2 (Free-base equivalent, FBE) q2w iv infusion, escalating to 70 mg/m2 FBE q2w, if tolerated. Results 30 pts (10 per cohort) were enrolled: 29 received >1 dose nal-IRI 50 mg/m2 FBE (median age 53 yrs, range 29-70 yrs). Median number of cytotoxic therapies prior to study entry was 3. The most frequent treatment emergent adverse events (TEAEs) were gastrointestinal disorders (all cohorts, 100%), primarily diarrhea (C-1, 100% / C-2, 100% / C-3, 70%), nausea (C-1, 80% / C-2, 56% / C-3, 30%), and vomiting (C-1, 60% / C-2, 33% / C-3, 30%). The incidence of neutropenia was low (C-1, 10% / C-2, 0% / C-3, 10%), all grade 1 / 2. Most common grade 3 TEAEs were diarrhea (28%), nausea (17%), fatigue (14%), hypokalemia (10%) and asthenia (10%), with none reported as grade 4. No grade 5 TEAEs were reported. Partial response (per RECIST) was observed in 10 pts for an objective response rate (ORR) of 35% (C-1, 40% / C-2, 33%) / C-3, 30%). Stable disease was observed in 5 pts (17%). Duration of Response (median, months) was C-1, 7.5 (6.4-13.0) / C-2, 5.6 (3.7-7.4) / C-3, 4.1 (0.0-22.2, extracranial: RECIST) / C-3, 1.8 (0.0-1.9, intracranial: mRECIST). Table 1.Study Demographics, Adverse Events, and Best Overall ResponseDemographicsCohort 1ER+ and/or PR+ Breast Cancern=10Cohort 2Triple Negative Breast Cancern=10Cohort 3Breast Cancer with Active Brain Metastasisn=10Total PopulationN=30Gender, Female, n (%)10 (100%)10 (100%)10 (100%)30 (100%)Age, Years Median (range)56 (49-68)52.5 (37-70)45.5 (29-63)53 (29-70)Race, n (%)WhiteBlack/AfricanOther8 (80%)02 (20%)8 (80%)1 (10%)1 (10%)7 (70%)1 (10%)2 (20%)23(77%)2 (7%)5(16%)Months Since Metastatic diagnosis, Months Median (Range)63.7 (16-87)20.7 (0-34)32.4 (8-55)24.0 (0-87)Number of Prior Cytotoxic Anti-cancer Regimens Median (Range)3.0 (1-6)3.0 (0-5)32.4 (1-6)3.0 (0-6)Safety PopulationCohort 1ER+ and/or PR+ Breast Cancern=10Cohort 2Triple Negative Breast Cancern=9Cohort 3Breast Cancer with Active Brain Metastasisn=10Total PopulationN=29ExposureTreatment Duration, Weeks Median (range)6.1 (0-78)12.3 (0-49)13.9 (1-105)12.3 (0-105)Adverse EventsAny TEAE10 (100%)9 (100%)10 (100%)29 (100%)Grade 38 (80%)6 (67%)10 (100%)20 (69%)Grade 41 (10%)06 (60%)3 (10%)TEAE Related to nal-IRI10 (100%)8 (89%)10 (100%)28 (97%)Grade > 36 (60%)3 (33%)3 (30%)12 (41%)TEAE Related to nal-IRILeading to Dose Adjustment*7 (70%)3 (33%)4 (40%)14 (48%)SAEs6 (60%)4 (44%)7 (70%)17 (59%)SAE Related to nal-IRI4 (40%)1 (11%)1 (10%)6 (21%)Duration of Objective ResponseRECIST 1.1RECIST 1.1RECIST 1.1mRECISTMonths Median (Range)7.5 (6.4-13.0)5.6 (3.7-7.4)4.1 (0.0-22.2)1.84 (0.0-1.9)Best Overall ResponseRECISTRECISTRECISTmRECISTComplete Response (CR)0000Partial Response (PR)4 (40%)3 (33%)3 (30%)3 (30%)Stable Disease (SD)03 (33%)2 (20%)3 (30%)Progressive Disease (PD)5 (50%)2 (22%)3 (30%)2 (20%)Not Evaluable (NE)1 (10%)1 (11%)2 (20%)2 (20%)Objective Response RateCR+PR(95% CI)4 (40%)12.2 -73.83 (33%)7.5-70.73 (30%)6.7-65.33 (30%)(6.7-65.3)*n=1 patient in Cohort 1 discontinued treatment due to TEAE related to treatment with nal-IRI CI, Confidence Interval; nal-IRI, Irinotecan Liposome Injection; SAE, Serious Adverse Event; TEAE, Treatment Emergent Adverse EventSystemic tumor response was evaluated according to RECIST version 1.1CNS tumor response was evaluated according to mRECIST (Anders C. et al., Breast Cancer Res Treat, 2014: 146(3):557-66) Conclusion nal-IRI monotherapy 50g/m2 FBE Q2W appears well tolerated, and achieved >30% ORR for systemic and CNS disease among heavily pre-treated mBC pts regardless of receptor status. Citation Format: Jasgit Sachdev, Pamela Munster, Donald Northfelt, Hyo S. Han, Cynthia MA, Fiona Maxwell, Tiffany Wang, Bruce Belanger, Bin Zhang, Yan Moore, Carey Anders. Phase I expansion study of irinotecan liposome injection (nal-IRI) in patients with metastatic breast cancer (mBC) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr CT048.

NAPOLI-1 (NCT01494506) was a phase III study of liposomal irinotecan (nal-IRI) plus 5-fluorouracil/leucovorin (5-FU/LV) in patients with metastatic pancreatic ductal adenocarcinoma (mPDAC) previously treated with gemcitabine-based therapy. This post hoc analysis of NAPOLI-1 aimed to develop a predictive nomogram for overall survival (OS) at 6 and 12 months. Analyses were derived from all patients in NAPOLI-1 randomized to receive nal-IRI+5-FU/LV, nal-IRI monotherapy, or 5-FU/LV combination therapy. OS was associated with baseline factors using univariate and multivariable Cox analyses. A predictive nomogram was derived and validated using a concordance index and calibration plots. The univariate analyses identified 21 independent factors that contributed to OS, with eight factors significantly associated with OS. The Karnofsky Performance Score contributed the largest number of points (100), followed by presence of liver metastasis (98) and randomization to nal-IRI+5-FU/LV (96). The other baseline factors showing effects were albumin (g/dL), neutrophil/lymphocyte ratio, carbohydrate antigen 19-9 (U/mL), disease stage at diagnosis, and body mass index (kg/m2). The nomogram was used to predict the 6- and 12-month survival probability. The mean absolute errors between the observed and predicted probabilities for OS at 3, 6, and 9 months were 0.07, 0.08, and 0.07, respectively. This nomogram, based on NAPOLI-1, provides additional insight to aid decision-making for patients with mPDAC after previous gemcitabine-based therapy.

Nanoliposomal irinotecan (nal‐IRI) is a liposomal formulation of irinotecan with a longer half‐life (t1/2), higher plasma total irinotecan (tIRI), and lower SN‐38 maximum concentration (Cmax) compared with nonliposomal irinotecan. Population pharmacokinetic (PK) analysis of nal‐IRI was performed for tIRI and total SN‐38 (tSN38) using patient samples from six studies. PK‐safety association was evaluated for neutropenia and diarrhea in 353 patients. PK‐efficacy association was evaluated from a phase III study in pancreatic cancer NAPOLI1. Efficacy was associated with longer duration of unencapsulated SN‐38 (uSN38) above a threshold and higher Cavgof tIRI, tSN38, and uSN38. Neutropenia was associated with uSN38Cmaxand diarrhea with tIRICmax. Baseline predictive factors were race, body surface area, and bilirubin. Analysis identified PK factors associated with efficacy, safety, and predictive baseline factors. The results support the benefit of nal‐IRI dose of 70 mg/m2(free‐base; equivalent to 80 mg/m2salt base) Q2W over 100 mg/m2Q3W.

TPS482 Background: Two combination chemotherapy regimens have emerged as standard of care options for first-line treatment of mPAC: 5-fluorouracil (5-FU)/leucovorin (LV) + irinotecan + oxaliplatin (FOLFIRINOX), and nab-paclitaxel + gemcitabine. Nal-IRI (MM-398) is a nanoliposomal formulation of irinotecan. In a randomized phase 3 study (NAPOLI-1), of patients with mPAC who had been previously treated with gemcitabine-based therapy, nal-IRI + 5-FU/LV demonstrated its safety and significant clinical activity, increasing overall survival (OS) and progression-free survival (PFS) relative to 5-FU/LV. The goal of this current study is to determine the preliminary safety and efficacy of nal-IRI+ + 5-FU/LV with or without oxaliplatin as compared to nab-paclitaxel + gemcitabine in previously untreated patients with mPAC. Methods: This open-label, phase 2 comparative study will be conducted in two parts. Part 1 is a safety run-in of a nal-IRI+5-FU/LV + oxaliplatin regimen. The safety run-in will enroll small cohorts of patients following a traditional 3 + 3 dose escalation design to confirm the target dose of oxaliplatin (n = ~6-18). The primary objective of Part 1 is the safety and tolerability of nal-IRI + 5FU/LV + oxaliplatin. Part 2 is a randomized, efficacy study of a nal-IRI + 5-FU/LV + oxaliplatin regimen (Arm 1), the nal-IRI + 5-FU/LV combination that previously demonstrated efficacy in the NAPOLI-1 trial (Arm 2), versus a nab-paclitaxel + gemcitabine control arm (Arm 3) (n = ~156-168). The primary objective of Part 2 is to assess the efficacy of nal-IRI-containing regimens in first-line mPAC patients compared to nab-paclitaxel + gemcitabine using the progression-free survival (PFS) rate at 24 weeks as the primary endpoint. Secondary of part 1 is a PK study and Part 2 secondary endpoints will include OS, PFS, objective response rate (per RECIST, v1.1), decrease in CA19-9 levels and quality of life assessments. Clinical trial information: NCT02551991.