Recombinant interleukin-2 and interferon-alpha-2a in pretreated advanced soft-tissue sarcomas

Area of Science:

• Oncology
• Immunotherapy
• Pharmacology

Background:

• Advanced soft tissue sarcomas (STS) have limited treatment options after failure of conventional chemotherapy.
• Cytokine therapy, including Interleukin-2 (IL-2) and Interferon-alpha (IFN-alpha), has shown potential in cancer treatment.
• Investigating novel combinations of cytokines in pre-treated STS patients is crucial for improving outcomes.

Purpose of the Study:

• To evaluate the safety and efficacy of combined subcutaneous recombinant Interleukin-2 (rIL-2) and intramuscular recombinant alpha-2a-interferon (r-alphaIFN) in patients with advanced soft tissue sarcomas.
• To assess the immunological effects, specifically the changes in natural killer (NK) cell populations, during combination cytokine therapy.
• To determine the clinical response and survival in pre-treated STS patients receiving this novel immunotherapy regimen.

Main Methods:

• A phase II outpatient study was conducted involving 14 patients with advanced STS previously treated with chemotherapy.
• Concomitant administration of rIL-2 (subcutaneous) and r-alphaIFN (intramuscular) was given for 3 weeks, followed by r-alphaIFN alone for 2 weeks.
• Dose escalation of rIL-2 was performed, and toxicity, clinical response (stable disease), survival, and immunological parameters (CD16+ NK cells) were monitored.

Main Results:

• Moderate toxicity was observed, primarily related to rIL-2 dosage, with side effects including abnormal liver function tests, fever, fatigue, and nausea/vomiting.
• In 11 evaluable patients, stable disease (SD) was achieved, with a median duration of 9 weeks (range 4-43 weeks).
• A significant increase in the percentage and absolute number of CD16+ lymphocytes (NK cells) was noted in most patients, indicating immune system activation.

Conclusions:

• The combination of rIL-2 and r-alphaIFN can be administered with minimal to moderate toxicity in pre-treated, immunocompromised advanced STS patients on an outpatient basis.
• The regimen demonstrated acceptable clinical results, characterized by stable disease and prolonged survival.
• The observed increase in NK cells suggests a potential immunomodulatory mechanism contributing to the clinical outcomes in this challenging patient population.