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At least 73 records · Page 4Linked to original sources
PubMed1992

Pyrimethamine alone as maintenance therapy for central nervous system toxoplasmosis in 38 patients with AIDS.

We retrospectively assessed the efficacy of maintenance therapy with pyrimethamine alone in 38 patients with AIDS and central nervous system (CNS) toxoplasmosis. The diagnosis was based on clinical presentation and compatible CT scan abnormalities with subsequent response to therapy. Survival analysis was performed by the product limit method of Kaplan-Meier. Fourteen patients received maintenance therapy with 25 mg pyrimethamine per day (group 1), and 24 patients were treated with 50 mg per day (group 2). The median survival from initiation of maintenance therapy until death or end of the study for the entire study population was 32 weeks. Median survival in group 1 was 28 weeks, as compared with 36 weeks in group 2 (p = 0.34). Relapses occurred in 12 patients, six in group 1 and six in group 2. There was no significant difference in failure-free survival between the two treatment groups (p = 0.09). One patient in group 1 and two patients in group 2 experienced severe toxicity, requiring discontinuation of therapy. All three patients relapsed and died. Two patients in group 2 who stopped treatment on their own initiative also had relapses. Thus, all five patients who discontinued therapy had relapses. Five of 13 patients in group 1 and two of 20 patients in group 2 relapsed during continuous therapy with pyrimethamine (p = 0.13); these seven patients responded to reintroduction of combination therapy (n = 6) or treatment with 50 mg pyrimethamine per day (n = 1). The results of our retrospective analysis suggest that maintenance therapy with oral pyrimethamine, 50 mg per day, in AIDS patients with CNS toxoplasmosis is effective.

Acquired Immunodeficiency Syndrome↗
PubMed2004

Maintenance therapy with interferon-alpha 2b, cyclophosphamide, and prednisone in aggressive diffuse large cell lymphoma.

Maintenance therapy in patients with aggressive malignant lymphoma using biological modifiers remains uncertain. We conducted a controlled clinical trial to evaluate the efficacy and toxicity of interferon-alpha 2b, cyclophosphamide, and prednisone as maintenance therapy in patients with aggressive diffuse large B cell lymphomas in complete remission after aggressive chemotherapy. In an intent-to-treat analysis, 169 patients were eligible for this study; the end points were event-free survival (EFS) and overall survival (OS). With a median follow-up of 49.3 months, no statistical differences were observed and actuarial curves at 5 years showed that EFS was 71% (95% confidence interval [CI], 63-79%) for patients who received maintenance compared to 63% (95% CI, 59-71%) for patients in control group (p = 0.05). No statistical differences were observed in OS between maintenance arm: 84% (95% CI, 78-89%) and control group 83% (95% CI, 77-88%) in control group (p = 0.2). All patients received the maintenance therapy as planned and in time, thus dose intensity was considered 1.0 in all cases. Acute toxicity was mild, and no delay or suspension of treatment was necessary. Late toxicity was not evident until now. We conclude that use of maintenance therapy combining interferon-alpha 2b, cyclophosphamide, and prednisone is not useful in patients with aggressive lymphoma if they had been treated with aggressive combined chemotherapy.

Adult↗
PubMed2004

Infliximab maintenance therapy for fistulizing Crohn's disease.

BACKGROUND: Infliximab, a monoclonal antibody against tumor necrosis factor, is an effective maintenance therapy for patients with Crohn's disease without fistulas. It is not known whether infliximab is an effective maintenance therapy for patients with fistulas. METHODS: We performed a multicenter, double-blind, randomized, placebo-controlled trial to evaluate the efficacy of infliximab maintenance therapy in 306 adult patients with Crohn's disease and one or more draining abdominal or perianal fistulas of at least three months' duration. Patients received 5 mg of infliximab per kilogram of body weight intravenously on weeks 0, 2, and 6. A total of 195 patients who had a response at weeks 10 and 14 and 87 patients who had no response were then randomly assigned to receive placebo or 5 mg of infliximab per kilogram every eight weeks and to be followed to week 54. The primary analysis was the time to the loss of response among patients who had a response at week 14 and underwent randomization. RESULTS: The time to loss of response was significantly longer for patients who received infliximab maintenance therapy than for those who received placebo maintenance (more than 40 weeks vs. 14 weeks, P<0.001). At week 54, 19 percent of patients in the placebo maintenance group had a complete absence of draining fistulas, as compared with 36 percent of patients in the infliximab maintenance group (P=0.009). CONCLUSIONS: Patients with fistulizing Crohn's disease who have a response to induction therapy with infliximab have an increased likelihood of a sustained response over a 54-week period if infliximab treatment is continued every 8 weeks.

Adult↗
PubMed1999

[Successful treatment of pleuritis carcinomatosa using combination therapy of 5'-DFUR, MPA and CPA as maintenance therapy].

A 44-year-old female patient with inoperable, local advanced left breast cancer was treated with 3 cycles of high dose CAF therapy followed by combination therapy of 5'-DFUR, MPA and CPA. The patient was discharged after receiving 3 cycles of high-dose CAF therapy and continued to receive daily oral doses of 5'-DFUR (800 mg), MPA (800 mg), and CPA (100 mg) for 15 months. After 3 cycles of high-dose CAF therapy, tumor marker (CEA, CA 15-3) levels were reduced. Six months later, after 3 cycles of high-dose CAF therapy, the tumor marker levels were within the normal range. No serious side effects were observed during chemotherapy. The patient enjoyed a good quality of life. We thus confirmed that this combination regimen was effective as a maintenance therapy for local advanced breast cancer.

Adenocarcinoma↗
PubMed1997

Ganciclovir. A pharmacoeconomic review of its use as intravenous or oral maintenance therapy in the management of cytomegalovirus retinitis in patients with AIDS.

Cytomegalovirus retinitis, an opportunistic infection caused by the herpesvirus cytomegalovirus, is a major cause of illness in patients with advanced AIDS. As infected patients require long term drug treatment to delay disease progression and minimise loss of vision, the disease is associated with substantial treatment costs which considerably increase overall expenditure on AIDS-related health care. During the last decade, intravenous ganciclovir has been a mainstay of treatment for patients with cytomegalovirus retinitis. However, notwithstanding its demonstrated efficacy as maintenance therapy for this condition, long term intravenous drug administration is both inconvenient and uncomfortable for many patients. Moreover, neutropenia and catheter-related infections have been reported commonly in patients receiving ganciclovir via the intravenous route. To overcome the limitations of intravenous ganciclovir, an oral formulation of the drug has been developed for use as maintenance therapy. In comparative clinical trials, both intravenous and oral ganciclovir maintenance therapy slowed disease progression and preserved visual acuity in patients with stabilised cytomegalo-virus retinitis, although there was evidence that the intravenous formulation was more effective in terms of delaying recurrence of active disease. This suggests that oral ganciclovir use should be limited to the treatment of patients without evidence of immediately sight-threatening cytomegalovirus retinitis. Three published cost analyses, which were based on efficacy and tolerability data derived from 2 randomised, comparative clinical trials, have shown that oral ganciclovir maintenance therapy offers cost advantages over intravenous maintenance therapy, despite the higher acquisition cost of the oral formulation. The higher overall costs of intravenous maintenance treatment, compared with oral therapy, were attributed to higher drug administration and adverse event treatment costs. In one analysis, estimated lifetime treatment costs of oral maintenance therapy were 25.2% lower than those of intravenous maintenance treatment. As yet, no formal cost-effectiveness evaluations of oral and intravenous ganciclovir have been published. Few published data are available regarding the relative effects of intravenous and oral ganciclovir on quality of life. However, in a health state utility analysis, there was a large overall preference among HIV-infected individuals for oral over intravenous maintenance treatment. In conclusion, oral ganciclovir appears to be a cost-saving and patient-preferred alternative to its intravenous counterpart for the maintenance therapy of AIDS patients with stabilised cytomegalovirus retinitis in whom there is no evidence of sight-threatening disease.

Acquired Immunodeficiency Syndrome↗
PubMedDate not supplied

Long-term follow-up of a cohort of HIV-infected patients who discontinued maintenance therapy for cytomegalovirus retinitis.

PURPOSE: To determine the long-term safety of discontinuation of maintenance therapy for cytomegalovirus retinitis (CMVR) and to identify predictors for relapse. METHOD: This was a prospective cohort study. Patients with treated CMVR who responded to HAART were followed by ophthalmologic assessment, markers for CMV replication (blood and urine cultures, CMV antigenemia, CMV DNA by PCR), and in vitro lymphoproliferative responses to CMV and other antigens after discontinuation of CMVR maintenance therapy. RESULTS: 23 patients were followed a median of 34 (range, 5-61) months. Median CD4 count was 321/mm3 at enrollment and 395/mm3 at last follow-up. HIV RNA was <50 copies/mL in 78% of patients at enrollment and 65% at last follow-up. One CMVR reactivation occurred at 12 months at a CD4 count of 395/mm3 (21%) and HIV RNA <50 copies/mL. Urine cultures were a poor predictive marker for reactivation. Other CMV replication markers had good negative predictive value. 96% of patients had a good lymphoproliferative response to CMV antigen in vitro. CONCLUSION: Maintenance therapy for CMVR can safely be discontinued in patients who have responded to HAART. Combining our results with the published literature, the risk of reactivation is estimated at 0.016 per person year of follow-up. Markers to predict relapse and the need for re-initiation of maintenance therapy are not yet identified.

AIDS-Related Opportunistic Infections↗
PubMed1996

Cytomegalovirus retinitis in AIDS patients: a comparative study of intravenous and oral ganciclovir as maintenance therapy.

OBJECTIVES: To compare the safety and efficacy or oral ganciclovir with intravenous ganciclovir for the maintenance therapy of cytomegalovirus (CMV) retinitis in AIDS patients. DESIGN: Multicenter, randomized, open-label study, with both masked and unmasked ophthalmic assessments. METHODS: Patients with AIDS and stable CMV retinitis were randomized after an induction course of intravenous ganciclovir (5 mg/kg twice daily) to receive maintenance therapy with oral ganciclovir (500 mg six times daily) or intravenous ganciclovir (5 mg/kg once daily). MAIN OUTCOME MEASURE: The primary endpoint of the study was time to progression of CMV retinitis from the start of maintenance therapy. RESULTS: The mean time to progression, evaluated by funduscopy was 109 days for the intravenous group, and 86 days for the oral group (P = 0.02). The masked photographic assessment revealed shorter time to progression for both oral and intravenous groups, as compared with funduscopy data, and showed no significant difference between the two treatment groups: 62 days for intravenous ganciclovir and 51 days for oral ganciclovir (P = 0.15). Diarrhea and neutropenia were the most frequent reported events in both groups, with the incidence of sepsis more than double in the intravenous compared with the oral ganciclovir group (3 versus 8.5%). CONCLUSIONS: Oral ganciclovir offers a reasonable alternative to intravenous ganciclovir for the maintenance therapy of CMV retinitis in AIDS patients.

AIDS-Related Opportunistic Infections↗
PubMedDate not supplied

6-Mercaptopurine cumulative dose: a critical factor of maintenance therapy in average risk childhood acute lymphoblastic leukemia.

A multivariate survival analysis including gender, age, log white blood cell (WBC) count, liver and spleen size at diagnosis, mean log WBC count during maintenance therapy, and the prescribed cumulative doses of 6-mercaptopurine (6-MP), methotrexate (MTX), vincristine (VCR), and prednisone (PDN) during maintenance therapy was performed on 53 children with average-risk acute lymphoblastic leukemia (ALL). The 6-MP cumulative dose prescribed during maintenance therapy resulted in the most important statistically significant independent prognostic factor. Patients who received less than the median cumulative dose of 6-MP (86% of planned protocol dose) fared significantly worse than the other patients, regardless of WBC count at diagnosis, gender, age, and other factors studied. Therefore, 6-MP cumulative dose during maintenance therapy may be the critical factor for effective maintenance therapy in childhood ALL.

Adolescent↗
PubMed1997

Maintenance therapy with cisapride after healing of erosive oesophagitis: a double-blind placebo-controlled trial.

BACKGROUND: There are few data on the role of prokinetic agents as maintenance therapy in moderately severe reflux oesophagitis despite the high relapse rate of this condition after healing. AIMS: To determine whether cisapride is more effective than placebo as maintenance therapy after healing of moderate erosive oesophagitis in two respects: first, in preventing symptomatic relapse and preserving quality of life; and, second, in improving oesophageal motor function. PATIENTS: Forty-two patients whose grade II-III oesophagitis had been healed with omeprazole were randomized to receive either cisapride 20 mg nocte or placebo for 6 months. Oesophageal pH monitoring and manometry were performed before starting maintenance therapy and after 4 weeks, and symptomatic status and quality of life were assessed at weeks 0, 4, 13 and 26. RESULTS: After 4 weeks of maintenance therapy, lower oesophageal sphincter pressure improved in the cisapride group (16.4-21.9 mmHg, P = 0.01) but not in the placebo group (25.5-22.7 mmHg, P = 0.2). Oesophageal pH monitoring showed no significant changes in either group. Sixteen (76%) cisapride patients and 12 (57%) placebo patients withdrew within 4 weeks owing to symptomatic relapse (P = 0.2). After 26 weeks, 21 (100%) cisapride and 17 (81%) placebo patients had relapsed (log-rank analysis of survival time P = 0.07). Quality of life parameters deteriorated in both treatment groups to a similar degree. CONCLUSION: Maintenance therapy with cisapride 20 mg nocte improves the lower oesophageal sphincter pressure in patients whose oesophagitis has been healed with omeprazole. However, cisapride is no better than placebo in preventing symptomatic relapse or deterioration in quality of life.

Adult↗
PubMed2006

Oral betamimetics for maintenance therapy after threatened preterm labour.

BACKGROUND: Some women who have threatened to give birth prematurely, subsequently settle. They may then take oral tocolytic maintenance therapy to prevent preterm birth and to prolong gestation. OBJECTIVES: To assess the effects of oral betamimetic maintenance therapy after threatened preterm labour for preventing preterm birth. SEARCH STRATEGY: We searched the Cochrane Pregnancy and Childbirth Trials Register (June 2005) and MEDLINE (from 1966 to August 2003). SELECTION CRITERIA: Randomised controlled trials comparing oral betamimetic with alternative tocolytic therapy, placebo or no therapy, for maintenance following treatment of threatened preterm labour. DATA COLLECTION AND ANALYSIS: Two review authors independently applied the selection criteria and carried out data extraction and quality assessment of studies. MAIN RESULTS: Eleven randomised controlled trials (RCTs) were included. No differences were seen for admission to the neonatal intensive care unit when betamimetics were compared with placebo (relative risk (RR) 1.29, 95% confidence interval (CI) 0.64 to 2.60; one RCT of terbutaline with 140 women) or with magnesium (RR 0.80, 95% CI 0.43 to 1.46; one RCT of 137 women). The rate of preterm birth (less than 37 weeks) showed no significant difference in four RCTs, two comparing ritodrine with placebo/no treatment and two comparing terbutaline with placebo/no treatment (RR 1.08, 95% CI 0.88 to 1.32, 384 women). No differences between betamimetics and placebo, no treatment or other tocolytics were seen for perinatal mortality and morbidity outcomes. Some adverse effects such as tachycardia were more frequent in the betamimetics groups than the groups allocated to placebo, no treatment or another type of tocolytic. AUTHORS' CONCLUSIONS: Available evidence does not support the use of oral betamimetics for maintenance therapy after threatened preterm labour.

Administration, Oral↗
PubMed2005

Esomeprazole 20 mg vs. pantoprazole 20 mg for maintenance therapy of healed erosive oesophagitis: results from the EXPO study.

BACKGROUND: Following initial healing of erosive oesophagitis, most patients require maintenance therapy to prevent relapse. AIM: To compare endoscopic and symptomatic remission rates over 6 months' maintenance therapy with esomeprazole or pantoprazole (both 20 mg once daily) in patients with healed erosive oesophagitis. METHODS: Patients with symptoms of gastro-oesophageal reflux disease and endoscopically confirmed erosive oesophagitis at baseline were randomized to receive esomeprazole 40 mg or pantoprazole 40 mg for up to 8 weeks. Patients with healed erosive oesophagitis and free of moderate/severe heartburn and acid regurgitation at 4 weeks or, if necessary, 8 weeks entered the 6-month maintenance therapy phase of the study. RESULTS: A total of 2766 patients (63% men; mean age 50 years) received esomeprazole 20 mg (n = 1377) or pantoprazole 20 mg (n = 1389) and comprised the intention-to-treat population. Following 6 months of treatment, the proportion of patients in endoscopic and symptomatic remission was significantly greater for those receiving esomeprazole 20 mg (87.0%) than pantoprazole 20 mg (74.9%, log-rank test P < 0.0001). Esomeprazole 20 mg produced a higher proportion of patients free of moderate to severe gastro-oesophageal reflux disease symptoms and fewer discontinuations because of symptoms than pantoprazole 20 mg (92.2% vs. 88.5%, P < 0.001). CONCLUSIONS: Esomeprazole 20 mg is more effective than pantoprazole 20 mg for maintenance therapy following initial healing of erosive oesophagitis and relief of gastro-oesophageal reflux disease symptoms.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed1993

Maintenance therapy for peptic ulcer--who needs it?

Until recently, peptic ulcer disease implied lifelong susceptibility to symptomatic, asymptomatic or complicated ulcer recurrences. Only about 50% of the ulcers seen endoscopically ever become symptomatic. Asymptomatic ulcers appear clinically unimportant, except in the setting of aspirin (ASA) or NSAID use, where they may lead without warning to fatal complications. Until recently, ulcer disease could not be cured medically: no drug has been shown to prevent ulcer complications occurring in patients taking ASA/NSAIDs. Low-dose maintenance therapy with H2-antagonists reduces recurrences and complications, but is expensive and requires indefinite use. Other anti-ulcer drugs have not been studied enough to conclude with confidence that they are similarly effective. Over 80% of recurrences are infrequent and can be treated when they occur n 20% of ulcer patients have 3 recurrences/yr, ulcer complications, or such poor health that recurrence might prove fatal. Ulcers recurring during maintenance therapy rarely complicate and heal with increasing and maintaining dosage. Eradication of H. Pylori (HP) infection, while difficult, abolishes most recurrences without maintenance therapy. Maintenance therapy is therefore indicated principally when HP can not be eradicated. Surgery is rarely required for uncomplicated disease.

Adult↗
PubMed2006

Rituximab maintenance therapy in indolent NHL: a clinical review.

Rituximab maintenance therapy following successful induction has emerged as a highly effective treatment for follicular lymphoma. Several randomized trials have been conducted analyzing the impact of rituximab maintenance compared to observation alone on treatment outcome. These studies have been conducted in patients receiving single-agent rituximab, standard chemotherapy or rituximab plus chemotherapy as initial cytoreduction, in both previously treated and untreated patients. In all the trials, rituximab maintenance resulted in a clinically and statistically significant benefit in clinical endpoints such as progression-free survival. Moreover, first data indicate that rituximab maintenance can prolong overall survival in patients with follicular lymphoma. These data have established rituximab maintanance as an important part of multimodal therapeutic strategies. Ongoing studies will help to determine the best schedule for the maintenance therapy in the treatment of follicular lymphoma.

Antibodies, Monoclonal↗
PubMed2006

Safety of rituximab maintenance therapy in follicular lymphomas.

The human/mouse chimeric monoclonal antibody rituximab has been used extensively in treatment of hematologic malignancies, and its efficacy and safety are well established, both as single-agent therapy and when used in combination with chemotherapy. Mild-to-moderate, transient infusion-related reactions are the most common adverse event, and rituximab does not add significantly to the toxicity of chemotherapy. Rituximab maintenance therapy has now emerged as an effective treatment for follicular lymphoma. Patients on rituximab maintenance therapy receive regular doses of rituximab for periods up to 2 years after initial induction therapy and are completely depleted of B-cells throughout this time, although B-cells eventually recover when maintenance treatment is stopped. In randomized trials of rituximab maintenance therapy versus observation after induction with single-agent rituximab, standard chemotherapy or rituximab plus chemotherapy, patients receiving rituximab maintenance therapy did not experience significantly greater toxicity than those in the observation arms, and no cumulative or unexpected toxicities were observed. Findings to date thus indicate that rituximab maintenance therapy is well tolerated, but further assessment of the long-term effects of prolonged B-cell depletion is still required.

Animals↗
PubMed1998

Acute lymphoblastic leukemia: dental health of children in maintenance therapy.

The dental health of 41 children aged 4-16 years who were in maintenance therapy from acute lymphoblastic leukemia (ALL) was examined in relation to the period of time in maintenance. There was no significant difference in dental experience and salivary flow rate between the control group and patients with leukemia. Performed treatment index (PTI) and required treatment index (RTI) scores reflected that children, who were in maintenance therapy had insufficient dental care and needed more dental treatments. A statistically significant difference in salivary pH was found between the children, who were in maintenance therapy for 12-24 months and less than 12 months and also the control group; but the pH scores of all groups were observed in normal limits.

Adolescent↗
PubMed2006

Antiretroviral adherence and HIV treatment outcomes among HIV/HCV co-infected injection drug users: the role of methadone maintenance therapy.

OBJECTIVE: We examined the association of methadone maintenance therapy (MMT) with highly active antiretroviral therapy (HAART) adherence and HIV treatment outcomes among a cohort of HIV/HCV co-infected injection drug users (IDUs). METHODS: We obtained demographic, drug use, and addiction care history from the Vancouver Injection Drug User Study (VIDUS), which is an open cohort study of IDUs. The questionnaires were longitudinally linked to the British Columbia HIV/AIDS Drug Treatment Program to obtain HAART adherence and HIV treatment outcome data. There were 278 VIDUS participants who accessed HAART from August 1, 1996 to November 24, 2003. We constructed longitudinal logistic models using generalized estimating equations to examine the independent associations between methadone maintenance therapy and the following outcomes: HAART adherence; plasma HIV-1 RNA suppression; and CD4 cell rise of 100cells/mm(3). RESULTS: Among participants who reported at least weekly heroin use, MMT was independently associated with lower odds of subsequent weekly heroin use during the follow-up period (adjusted odds ratio; 95% confidence interval [AOR; 95% CI]: 0.24; 0.14-0.40). We also found that MMT was positively associated with adherence (AOR 1.52; 95% CI 1.16-2.00), HIV-1 RNA suppression (AOR 1.34; 95% CI 1.00-1.79), and CD4 cell count rise (AOR 1.58; 95% CI 1.26-1.99). CONCLUSIONS: Among HIV/HCV co-infected IDUs on HAART, enrollment in MMT was associated with reduced heroin use, and improved adherence, HIV-1 RNA suppression and CD4 cell count response. Integrating opiate addiction care and HIV care may provide improved health outcomes for this vulnerable population and should be further explored.

Adult↗
PubMed1996

[A randomized controlled study of maintenance therapy with (2"R)-4'-O-tetrahydropyranyladriamycin for advanced and recurrent breast cancer. Clinical Study Group of THP for Breast Cancer in Japan].

We conducted a randomized controlled study to evaluate the clinical usefulness of (2"R) -4'-O-Tetrahydropyranyladriamycin (THP)-based combination therapy subsequent to induction therapy which was consisted with THP, 5'-DFUR, and CPA in the treatment of advanced or recurrent breast cancer. In maintenance therapy, Arm C received CPA and TAM, and Arm T received these two drugs plus THP. Survival time of 50% for all cases in which maintenance therapy was conducted was 26.9 months in Arm T and 20.9 months in Arm C, showing no significant difference by the log-rank test (p = 0.64). Survival time in all cases in which therapy had been completed was 54.6 months in Arm T and 28.1 months in Arm C, showing a significant difference by the log-rank test (p = 0.03) although the number of cases was few. A few cases showed a decrease in total leukocyte count to below 2,000/mm3 at the time of induction therapy, but this was transient in all cases. No significant difference in count was noted between two arms at the time of maintenance therapy. However, many cases in Arm T showed decreased total leukocyte count and hemoglobin content, and thrombocytopenia. These results suggest that combination therapy including THP conducted as maintenance therapy after induction is useful in the prolongation of survival time in patients with advanced or recurrent breast cancer.

Adult↗
PubMed1995

2',5'-Oligoadenylate synthetase levels in patients with multiple myeloma receiving maintenance therapy with interferon alpha 2b do not correlate with clinical response.

In clinical trials with interferon alpha 2b (IFN-alpha 2b) as maintenance therapy for multiple myeloma, the therapeutic benefit is inconclusive. Although the mechanism(s) by which IFN-alpha 2b prolongs remission in some patients is unknown, 2',5'-oligoadenylate synthetase (2,5-A synthetase) has been used as an objective indicator that IFN-alpha 2b is active in vivo. The enzyme was assayed in cytosol preparations of peripheral blood mononuclear cells (MNCs) from 111 patients who were receiving IFN-alpha 2b and 54 patients who were not, using an assay which measures the conversion of [alpha-32P]ATP to triphospho(adenylyl 2',5')adenosine. 2,5-A synthetase activity was compared with response to intensive therapy and with duration of maintenance therapy. Seventy-three per cent of patients had measurable amounts of 2,5-A synthetase during the first 6 months of maintenance therapy. This percentage decreased with longer follow-up but not significantly. There was no difference between the magnitude of enzyme induction amongst patients who were in complete remission, partial response or who had no change in disease status following intensive therapy. Peripheral blood T cells were a major source of 2,5-A synthetase activity in patients receiving the cytokine. However, both T and B cells produced the enzyme following exposure to IFN-alpha in vitro. The data show that the level of 2,5-A synthetase in patients with multiple myeloma is not indicative of clinical response to IFN-alpha 2b.

2',5'-Oligoadenylate Synthetase↗