Alpha interferon raises serum beta-2-microglobulin in patients with multiple myeloma

MRC trial of alpha2b-interferon maintenance therapy in first plateau phase of multiple myeloma. MRC Working Party on Leukaemia in Adults

Plateau phase has been achieved in 64% of all newly diagnosed patients with multiple myeloma treated with the ABCM (adriamycin, BiCNU, cyclophosphamide and melphalan) regimen in the Medical Research Council (MRC) trials; this stable clinical stage of the disease is associated with no more than minimal symptoms. Several studies have found that alpha-interferon (alpha-IFN) maintenance therapy increases the duration of plateau phase, but it is less clear if this translates into prolonged survival. We report the effect of alpha-IFN on the duration of plateau phase and overall survival in a trial with 284 patients who were randomized to receive alpha2b-IFN (Intron-A) or no maintenance therapy during first plateau phase. The minimum follow-up after randomization was 21 months. There was no significant difference in the overall survival between the two treatment groups (X2=0.32, P=0.57). There was a trend towards longer relapse-free survival in the patients allocated alpha-IFN, but this trend to longer plateau phase was not statistically significant (X2 = 1.62, P = 0.2). Disease progression at relapse on alpha-IFN appears to be more severe with greater elevations from plateau levels of serum paraprotein (P = 0.06) and beta2-microglobulin (P= 0.03) levels. Physicians tended to start chemotherapy sooner after diagnosis of relapse when patients had received alpha-IFN (P = 0.16). Although, in common with most other studies, there is a trend for patients treated with alpha-IFN to have a longer plateau phase, this is counteracted by morbidity attributable to the treatment and a somewhat shortened survival post relapse. Meta-analysis of interferon trials is required to assess whether the minor trend for longer survival in patients maintained on alpha-IFN found in some studies is significant and, if so, the extent of this advantage.

Effects of alpha-interferon on serum beta-2-microglobulin

Beta-2-microglobulin (B2M) forms the small invariable light chain subunit of class I HLA antigens on the cell membrane of all nucleated cells. During the continuous turnover of the HLA molecules, B2M is shed from the cell membrane into blood. Lymphocytes are the main source of serum free B2M. Serum B2M concentration is increased in renal diseases, various malignant diseases and some inflammatory and autoimmune disorders. In lymphatic malignancies serum B2M has significant prognostic value. Interferons (IFNs) have the ability to enhance the expression of class I and II histocompatibility antigens. Accordingly, IFNs cause a rise in formation and release of B2M. Currently, treatment with IFN alpha is used in diseases, like multiple myeloma, where serum B2M measurements are used to assess tumor burden. We have measured serum B2M levels during IFN alpha treatment in patients with both multiple myeloma and chronic myeloproliferative diseases, and IFN alpha caused a significant increase in serum B2M. It can be concluded that use of IFN alpha abolishes the value of serum B2M as an indicator of disease activity.

The role of biotherapies (interleukins, interferons and erythropoietin) in multiple myeloma

During the last decade, the availability of large numbers of cytokines and growth factors has greatly favoured the use of biotherapies in several haematological disease. For MM, the majority of clinical studies have dealt with the use of IFN-alpha. From these studies it appears that IFN-alpha has a definite role in the treatment of MM especially in the setting of minimal residual disease, as maintenance therapy after response to conventional therapies or HDC followed by BMT procedures or PBSCI. Data on the use of EPO have consistently demonstrated the role of this growth factor in ameliorating the grade of anaemia as well as the quality of life of those MM patients whose disease is complicated by the presence of a severe or moderate anemia. Despite the large amount of experimental data indicating a role for IL-2 and IL-6 in controlling tumour growth, there are only a few clinical studies dealing with their use in MM. From these, it appears that IL-2 and anti-IL-6 antibodies should be further investigated as therapeutic tools useful in maintaining responses, because results show that they arrest tumour progression rather than aid, tumour regression. Finally, in the next years, there will be a wider diffusion of biotherapies in MM that should take into account the roles that IL-1 beta and TNF alpha play in myeloma cell proliferation and bone destruction and the finding that retinoic acid is capable of inhibiting the growth of human myeloma cells in vitro through modulation of IL-6 and its receptor.

No synergistic activity of epirubicin and interferon-alpha 2b in the treatment of hepatocellular carcinoma

Single-agent activity for anthracyclines reflected by response rates of 10%-30% has been reported in patients with advanced hepatocellular carcinoma (HCC). Preclinical data indicate that alpha-interferon could enhance the cytotoxic activity of the anthracycline Adriamycin or its analog epirubicin. In a phase I/II study, 31 patients with biopsy-proven inoperable HCC were treated with interferon-alpha 2b given s.c. at a dose of 3 x 10(6) units/m2 per day for 5 days per week plus weekly epirubicin given at 25 mg/m2 as an i.v. bolus. The protocol called for 4 consecutive weeks of treatment followed by 1 week off treatment. In all, 15 patients had been previously treated; 6 patients had failed hormonal therapy (tamoxifen), 5 patients had failed prior anthracycline treatment, and 4 patients had received chemoembolization of the tumor and had subsequently progressed. A total of 30 patients were evaluable for response. In all, 1 patient (3%) achieved a partial response for 8+ months and 11 patients (35%) achieved stabilization of disease. Six patients had a fall in alphafetoprotein (AFP) values of > 50% during therapy. The median survival for all patients was 9.5 months (range, 3-34+ months). The main side effects were hematological toxicity and fever, both of which were considered tolerable. As an indicator of the immunostimulatory effects of interferon, an elevation in serum markers of inflammation [C-reactive protein (CRP), beta 2-microglobulin] was found in 15%-20% of patients. All patients had measurable Mx protein production during therapy, but these effects were not correlated to the clinical response. The clinical response rate achieved in this trial indicates that the combination of interferon and epirubicin, at least when used on the schedule reported herein, is not superior to treatment with either agent alone for patients with advanced HCC. However, single patients achieved a prolonged progression-free interval (8-10+ months) on this therapy, and it may therefore be an option for patients who have failed prior hormonal or single-agent anthracycline therapy.

Alpha interferon raises serum beta-2-microglobulin in patients treated for thrombocythaemia

Serum beta-2-microglobulin (b2m) levels were studied in 10 patients treated with alpha interferon (IFN) for thrombocythaemia associated with chronic myeloproliferative diseases. In eight patients the IFN treatment decreased the blood platelet level to < 600 x 10(9)/l. Serum b2m levels rose significantly and dose-dependently immediately after the onset of treatment, by a median maximal increase of 72% with IFN 3 MU every other day, and 95% with 3 MU daily. The b2m rise caused by IFN abolishes the value of serum b2m in states where b2m is used as an indicator of disease activity.