Pharmacoeconomic savings associated with alternate dosing strategy of nivolumab and ipilimumab combination therapy

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Background: Nivolumab (NIVO) plus ipilimumab (IPI) is a commonly used therapy for advanced melanoma. Original weight-based dosing of NIVO 1 mg/kg plus IPI 3 mg/kg (NIVO1+IPI3) was approved in 2017. Recently, the CHECKMATE 511 trial demonstrated improved tolerability of NIVO 3 mg/kg plus IPI 1 mg/kg (NIVO3 + IPI1) compared to the original dosing regimen without observed differences in efficacy.Objective: To determine the pharmacoeconomic implications of NIVO1+IPI3 and NIVO3+IPI1 with a dose banding strategy applied. Methods: Patients with advanced melanoma (N = 21) who received IPI and NIVO in combination between 4/2019 – 7/2019 were evaluated via a single-center retrospective chart review. A total of 118 checkpoint inhibitor doses (59 NIVO, 59 IPI) were analyzed.Weapplied a dose banding strategy to both NIVO1+IPI3 and NIVO3+IPI1 regimens to examine pharmaceutical expenditures using the two dosing regimens, whichincluded our organization 10% dose-vial rounding policy. Pharmaceutical expenditure using average wholesale price (AWP), which was $32.42 per mg of NIVO and $180.03 per mg of IPI, was calculated for each dosing strategy (NIVO1+IPI3 and NIVO3+IPI1). Results: The anticipated cost savings of patients receiving NIVO3+IPI1 combination therapy compared to NIVO1+IPI3, (both with dose rounding strategy applied), was $1,459,473 or >$70,000 per patient, representing a 47.2% savings from the original NIVO1 +IPI3 regimen (Table). Conclusions: In addition to improved tolerability and comparable efficacy for NIVO3+IPI1 vs NIVO1+IPI3, our study shows that adoption of the NIVO3+IPI1 regimen results in significant savings in drug costs. Considerations should be made in future combination trials to compare NIVO3+IPI1 as a treatment arm to NIVO1+IPI3 to see if comparable clinical results can be obtained with less toxicity and decreased pharmaceutical spending. [Table: see text]

A phase I/II study of pembrolizumab (Pem) and doxorubicin (Dox) in treating patients with metastatic/unresectable sarcoma

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Background: Patients with advanced soft tissue sarcomas (STS) treated with single agent Dox have a median progression-free survival (PFS) of 4.6 months (mo) and response rate (RR) of 14%. Dox sensitizes tumors to Pem through calreticulin release and killing of immunosuppressive cells. Thus we hypothesize that combining Dox + Pem will improve patient outcomes. Methods: A phase I/II trial (NCT02888665) evaluating Dox+Pem was designed for Dox naïve STS and select bone sarcomas with a 1° endpoints of safety (CTCAE v4.03) and response rate (RR) by RECIST 1.1. Patients received one “priming” dose of Pem (200mg IV) prior to starting Dox+Pem Q3wks. Dox+Pem was continued for up to 6 cycles, followed by Pem monotherapy for up to 2 years or progression. The phase I portion used a 3+3 design with 2 Dox doses (45 & 75 mg/m2), followed by a Simon 2-stage expansion. A retrospective study of patients treated at our center on non-ifosfamide containing Dox trials (DoxT) was performed in order to compare our observed PFS with a comparable historic population. Results: Treatment was well tolerated; detailed safety data will be presented. No additional cardiac risk was observed. No DLTs were observed during phase I and 75mg/m2 was selected as the phase 2 Dox dose. The study met criteria for expansion to the 2nd stage. Though the planned enrollment was 41, the study closed after 37 as it was clear that the RR (22% , including phase I patients) would not meet the phase 2 RR target of 29%. However, 59% of patients had stable disease (disease control rate = 81%) with tumor regression in a majority of patients. The median PFS on Dox + Pem was 8.1 mo (95% CI: 6.3, 10.8). Patients treated with Dox + Pem had a significantly longer median PFS compared to the DoxT cohort (4.1 mo, 95%CI 3.0 – 6.6, p < 0.001). Conclusions: Dox+Pem is well-tolerated. While this study failed to meet its 1° RR endpoint, a highly significant improvement in PFS was observed compared with historical controls. This is consistent with findings in other cancers, such as head & neck, where improved clinical outcomes were observed without significant increase in RR by RECIST. A randomized trial of Dox +/- Pem should be carefully considered in light of recent negative trials in STS. Clinical trial information: NCT02888665.

Prevalence of symptom clusters among sarcoma patients in active treatment

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Background: Cancer patients (pt) frequently experience symptoms from cancer or its treatment. Two or three co-occurring, uncontrolled symptoms (symptom clusters, SC), can worsen cancer pt morbidity and mortality. Although SC have been characterized in other cancer pts, little research has been conducted in sarcoma pts. Methods: SC were studied via retrospective chart review of adult sarcoma pts receiving treatment between 09/2018-01/2019 in a dedicated sarcoma clinic. Pts completed a 33-item, modified Patient Reported Outcomes-Common Terminology Criteria for Adverse Events (mPRO-CTCAE)-based review of systems (hereafter “form”) for ongoing clinical care with presence of individual symptoms defined as ≥“occasionally.” Demographic, disease and treatment specific data was collected; descriptive data (%’s) are presented. Results: Pts (n = 153 completing 321 forms) were median 57 years (range 20-81), 48% male, 68% white, with lower extremity (29%) or abdomen (46%) sarcoma with 67% receiving IV chemo (33% oral chemo), with the majority at full dose (77%). Most had leiomyosarcoma 18%, liposarcoma 14%, GIST 12%, or NOS 24% with 59% metastatic disease. Five SC triads occurring in > 25% of pts who fully completed one form were identified (see Table). Eighty-one pts completed 2 or more forms (mean 26.7 days from first to second form [std dev 17.7, range 2-77]) with 50-67% of evaluable pts having ongoing SC triads. Conclusions: Symptom clusters are common among sarcoma patients on active treatment. Future research should address optimal management of these clusters. Additional data, including severity/interference of symptoms, longitudinal changes and predictors of SC, will be presented.[Table: see text]