The outcome for patients with unresectable or metastatic soft tissue sarcoma (STS) is poor. Following failure from first-line doxorubicin based chemotherapy no standard therapy has been established. Combination treatment with docetaxel/gemcitabine (gem) has emerged as an effective regimen but administration is limited to fit patients only due to the toxicity profile. Nanoparticle albumin bound paclitaxel (nab-PC) was invented for avoidance of the toxicities related to polyethylated castor oil. In this context, we want to evaluate toxicity and antitumor effect of biweekly nab-PC 150mg/m2 / gem 1000mg/m2 administration in STS patients.
We conducted this proof-of-concept phase I trial to assess the safety of biweekly nab-PC/gem administration in the 2nd and 3rd line setting of STS.
As of 1 April 2019, 6 pts were treated within the phase I. Three pts were male (50%); median age was 67 yrs (range 44 – 72). The current total number of biweekly doses received is 29 (median biweekly doses per patient is 5, range 2 – 7). One dose reduction due to skin toxicity occurred. 3 pts remain on study, 3 stopped treatment due to treatment unrelated reasons (refusal, death unrelated to progression or toxicity and investigator’s decision). The most common treatment-emergent AEs Gr1-2 were fatigue (3 pts), alopecia (3 pts), and neutropenia (2 pts). There were no dose-limiting toxicities or discontinuations due to AEs. We were able to confirm the tolerability of the regimen and are currently accruing patients to a prospective single arm phase II trial. Treatment will be given biweekly until progression, unacceptable toxicity or patient withdrawal. The primary endpoint of the trial is progression-free rate (PFR) at 12 weeks. Secondary endpoints are PFS, overall survival and symptom-specific quality of life. A total of 8 Swiss sites will participate for a total of 37 patients, as required by Simon’s two-stage design.
These preliminary results indicate that biweekly administration of nab-PC/gem was well tolerated. The phase I established dose and schedule were selected for further evaluation in phase II trial.
Clinical trial identification
Legal entity responsible for the study
Swiss Group for Clinical Cancer Research (SAKK).
Swiss League Against Cancer, Celgene.
A. Digklia: Advisory / Consultancy, Travel / Accommodation / Expenses: Amgen, PharmaMar, Servier, BMS; Research grant / Funding (self), Research grant / Funding (institution): Research Funding Recipient Institution. C. Britschgi: Advisory / Consultancy: Roche, Pfizer,takeda,AstraZeneca. Y. Metaxas: Advisory / Consultancy: Roche, MSD, Pierre Fabre, Merck-Serono, BMS. F. Krasniqi: Advisory / Consultancy: Roche Pharma (Schweiz) AG, Mundipharma Medical Company (Schweiz), Celgene GmbH. A. Stathis: Travel / Accommodation / Expenses: Abvie, PharmaMar; Research grant / Funding (institution): Amgen, Bayer, Novartis, Roche, MEI-Pharma. T. Rordorf: Advisory / Consultancy: Bristol-Myers Squibb and Merck KGaA. N. Mach: Honoraria (institution), Advisory / Consultancy: Amgen, AstraZeneca, Bristol-Myers Squibb, F. Hoffmann-La Roche, Merck Sharp and Dohme, Merck Serono, Novartis, Pharma Mar, as well as honorarium for talks in a company’s organised public event from Bristol-Myers Squibb and Pharma Mar. C.A. Rothermundt: Advisory / Consultancy: BMS, Astellas Pharma Schweiz, GSK, Novartis, Roche, Pfizer, PharmaMar; Research grant / Funding (institution): Research Funding Recipient Institution. All other authors have declared no conflicts of interest.