Interferon a2 in follicular lymphoma

Interferon (IFN) a2 prolongs survival and remission in follicular lymphoma in specific circumstances, but is associated with significant toxicity, a meta-analysis suggests.Results from randomised studies of interferon a2 in follicular lymphoma differ widely, probably because of variability in patient populations and entry criteria. Published studies included differences in dose intensity and schedule of chemotherapy and interferon, use of radiotherapy and histological subtypes of lymphoma. Some trials had wide entry criteria, but one only included patients in complete remission from prior chemotherapy. This meta-analysis of 10 phase III studies of 1,922 patients included six studies where interferona2 was given as initial therapy, four when given as maintenance and four where it was given throughout.Results showed that addition of IFN a2 to initial chemotherapy did not influence overall response rate. Use of interferon a2 at any point appeared to prolong survival but there was significant heterogeneity between studies. The authors considered that one study was clearly an outlier as it had a greater survival than any other, possibly because it included only patients in complete response. In patients who did not respond, use of interferon a2 did not prolong survival. The authors considered that the effect of interferon a2 related to intensity of initial chemotherapy or interferon a2 and whether it was used as initial or maintenance therapy and it was likely that more than one factor was operating, but this could not be established from current data. They considered that the survival effect appeared to be a late effect.The authors noted that the meta-analysis results support the use of interferon a2 but there was significant clinical toxicity and it was difficult to relate the information to clinical practise. They concluded that treatments for follicular lymphoma may now include fludarabine based treatment, anti CD20, radioimmunotherapy and high-dose treatments and concluded that these may need to be tested in phase III trials with pegylated interferon which has fewer side-effects.Reference...