***TASK***
the task is to simplify the input abstract of a biomedical literature

***INPUT***
the input is the abstract of a biomedical literature

***OUTPUT***
the output is the simplified abstract for the input abstract of a biomedical literature

***DOCUMENTATION***

***EXAMPLES***

Input: Of 1777 potential studies evaluated, only two Randomized Control Trials (123 patients) were included. ß-interferon treatment compared to placebo did not show differences regarding the proportion of patients with progression of the disease (RR 0.89, 95% CI 0.55 to1.43), and it was associated with a greater frequency of treatment-related adverse events (RR 1.90, 95% CI 1.45-2.48). One of the trials evaluated the MRI secondary outcome pre-specified in the protocol. This trial showed that at two years the numbers of active lesions on brain MRI scan in ß-interferon arm were significantly lower than in placebo arm (weighted mean difference -1.3, 95% CI -2.15 to -0.45, P = 0.003); also, the number of participants with active lesions was significantly higher in placebo arm vs. ß-interferon arm at two years (RR 0.43, 95% CI 0.22 to 0.86, P = 0.02). Limited data on the effect of ß-interferon treatment on PPMS exists. Only two single-centre placebo controlled trials of interferon beta have been done. Based on this review, the included studies showed that ß-interferon treatment was not associated with reduced disability progression in PPMS patients. However, the trial population was too small to allow definitive conclusions on the efficacy of ß-interferon therapy in PPMS patients. Larger research studies need to be done in patients with PPMS in order to clarify whether ß-interferon is effective in this population.
Output:

Among the pertinent medical literature only  two studies, comprising  a total of 123 participants,  met the criteria of the methodological quality necessary for their inclusion in this review. Taking into account  the disability progression, the analysis of the data showed that INF beta treatment in  patients with PPMS was  not associated with a reduction of  this parameter during the first two years of therapy. Adverse effects, mainly flu-like symptoms and injection site reactions, occurred frequently and were the same as  reported by the many studies on   IFN beta treatments in MS patients with different types of the disease. It is worth nothing that the patients’ population analysed was too small to allow a definitive conclusion on the efficacy of IFN beta therapy  in PPMS.