A phase I clinical tolerance study of rDNA alpha 2 human interferon in patients with non-reticuloendothelial system malignancies

Experience with interferon alpha 2b combined with dacarbazine in the treatment of metastatic malignant melanoma

A prospectively randomized trial was undertaken to compare dacarbazine (DTIC) alone with DTIC plus interferon in patients with metastatic malignant melanoma. Of the 73 patients who entered on the study, 36 were randomized to receive DTIC alone and 37 were randomized to receive the combination DTIC plus interferon. The two sections were well balanced. There was more toxicity on the combination section, but no life threatening toxicity. The overall response rate for patients on DTIC was 20% (two complete and five partial responses) (95% CI 7-39%) and for patients on DTIC plus interferon was 50% (13 complete and four partial responses) (95% CI 26-72%) (p = 0.007). The median time to treatment failure, was significantly more in favour of the combination treatment (9 versus 2.5 months; p < 0.01, Mantel-Cox). The median survival of 16.7 versus 8 months was in favor of the combination treatment (p < 0.01). The reasons for the improved results with the combination treatment are discussed. The Eastern Cooperative Oncology Group is currently, based on the results of this study, investigating the role of interferon combinations in metastatic malignant melanoma.

Cardiotoxicity of interferon. A review of 44 cases

Cardiovascular complications have occurred in clinical trials of interferon. We review herein experience to date of cardiotoxicity with all types of interferons in cancer patients. The most common presentations of cardiotoxicity were cardiac arrhythmia, dilated cardiomyopathy, and symptoms of ischemic heart disease, including myocardial infarction and sudden death. The cardiac effects were not related to the daily dose, cumulative total dose, or period of therapy. Some of the patients in whom interferon has caused cardiovascular sequelae have had a history of coronary heart disease or have previously been given chemotherapy with drugs known to be cardiotoxic. In most of the patients, cardiac toxicity was reversible following the cessation of the drug therapy.

Clinical overview of alpha interferon. Studies and future directions

The clinical development of the alpha interferons has now progressed through initial Phase I and II trials into extensive controlled clinical trial designs. Alpha interferon has been a prototype of other biological agents that are now in clinical development. These agents operate through fundamentally different mechanisms of action than conventional chemotherapy and have produced a unique profile of side effects as well as response patterns. Time to response is generally longer than with chemotherapy, and dose-response and schedule-dependency questions continue to be explored for most tumor types. Although response rates have been low against most solid tumors when alpha interferon is used as a single agent, it has demonstrated a surprisingly wide range of efficacy in hematologic malignancies. These include tumors of presumed B-cell, T-cell, and myeloid lineages. In some diseases, e.g., hairy cell leukemia and chronic myelogenous leukemia, alpha interferon is broadly effective; it appears to considerably reduce or occasionally eliminate the malignant clone while normalizing the peripheral blood counts in most patients. In other diseases, alpha interferon appears destined to play a major role as part of combination therapy or in maintenance or consolidation therapy. In other disease settings, alpha interferon's role continues to be explored as part of combination therapy, adjuvant therapy, or as local-regional therapy. The full potential of alpha interferon as an antineoplastic agent will not be determined for many years. In this paper, the results from the first 5 years of widespread clinical testing are reviewed.

Low incidence of serum neutralizing factors in patients receiving recombinant alfa-2b interferon (Intron A)

The development of serum neutralizing factors against recombinant alfa-2b interferon (Intron A) was reviewed in a large clinical experience. In 537 patients receiving systemic therapy, neutralizing factors developed in only 13 (2.4 percent). In 1,326 patients who received intranasal administration and 154 with intralesional administration, the incidence was less than 1 percent. Patients in whom antibody developed had no predisposing characteristics that could be identified, no particular types of patients with cancer had a high rate of neutralizing factors, and two of 10 patients with cancer in whom neutralizing factor developed were still able to show clinical responses. In patients in whom neutralizing factor was present, there was no discernible difference in the incidence or severity of interferon side effects as compared with patients who had no demonstrable neutralizing factor levels. This form of recombinant alpha-2 interferon appears to have a very low antigenic potential.

Recombinant DNA human interferon alpha 2 in advanced breast cancer: a phase 2 trial

Effectiveness of recombinant DNA (rDNA) human interferon alpha 2 (IFN alpha 2) in advanced breast cancer was evaluated in 14 patients who had received prior endocrine and/or cytotoxic therapy. After randomization, 7 patients received IFN alpha 2 two million IU m-2 day-1, s.c., 3 times a week (schedule 1) and 7 patients received 50 million IU m-2 day-1, i.v., for 5 consecutive days, every 3 weeks (schedule 2). Treatment duration was 4-21 weeks in schedule 1 and 6-24 weeks (2-8 courses) in schedule 2. Regressions were not achieved with either schedule. Treatment was associated with significant toxicity and was more severe in schedule 2. Dose limiting toxicities were leukopenia, elevation of liver enzymes, hyperglycemia and fatigue. Serum IFN activity was low or undetectable in patients on schedule 1 and high in patients on schedule 2. At 24 h, serum IFN activity was detectable in only 1/6 patients on schedule 1 as compared to 3/7 patients on schedule 2. IFN neutralizing factors were detected in the serum of only 1 patient prior to treatment but none were detected in any of the patients during or after discontinuation of treatment (4-24 weeks). IFN alpha 2 increased the expression of both HLA class 1 antigens and beta 2 microglobulin in peripheral blood lymphocytes in vivo. This effect was dose related.