Maintenance Treatment with Interferon in Multiple Myeloma

Some clinical trials have shown that long-term treatment with alpha interferon (IFN) in patients with multiple myeloma can improve survival in comparison with patients not given IFN, but other studies have found no survival benefit in patients treated with IFN. We utilised the clinical material reported in these trials to conduct a meta-analysis on long-term survival. The survival curves published in each of these studies were analysed to determine the mean lifetime survival (MLS) for treated patients and controls using Gompertz’ extrapolation to infinity of the survival curves. Values of MLS were then pooled using standard meta-analytic techniques. Our meta-analysis showed that maintenance treatment with IFN did not improve MLS at levels of statistical significance. The MLS was 3.9 years per patient in the IFN group versus 3.4 years per patient in the controls (p = 0.095). Because the level of statistical significance was borderline, a lifetime cost-effectiveness analysis was undertaken to determine the cost per life-year gained using IFN. This cost was found to be around $US84 000 per life-year gained, a value suggesting an unfavourable pharmacoeconomic profile. We conclude that the survival advantage of maintenance treatment with IFN in myeloma patients, if any, has a small clinical relevance and demonstrates an intermediate or unfavourable pharmacoeconomic ranking.