Acrivastine: a review of its dermatopharmacology and clinical activity.

The general human and skin pharmacology of acrivastine, its clinical utility and some important concepts of the use of H1-antihistamines in dermatology are discussed. The drug has potent H1-antihistamic activity yet a low sedative profile as compared with first generation agents. Acrivastine is rapidly absorbed with peak inhibition of flare areas occurring at 90 min and peak activity against weals at 120 min after drug administration. No accumulation of the drug following multiple dosing has been demonstrated. Due to these effects the drug has a high level of patient acceptability and a high level of useful activity in a range of histamine-mediated dermatoses.

Acrivastine--an evaluation of initial and peak activity in human skin.

Twenty-four healthy volunteers were entered into a double-blind, crossover study conducted to establish the time of onset of action and the time to peak activity of acrivastine in suppressing the weal and flare responses to intradermally injected histamine. Volunteers received single doses of 8 mg acrivastine and placebo according to a fully randomized, balanced treatment plan. Acrivastine significantly (P less than 0.001) reduced both the weal and flare responses induced by histamine challenge 30 min after oral dosing, as compared with placebo. Peak inhibition of the flare response was seen at 90 min, and maximal suppression of the weal response occurred at 120 min after administration of acrivastine.

An evaluation of the antihistamine activity of acrivastine and its onset in human skin.

In a double-blind, two-period crossover study, 24 healthy volunteers were evaluated to establish the time of onset of action of activity of acrivastine in suppressing the weal and flare response to intradermally injected histamine. Volunteers received single doses of 8 mg acrivastine and placebo according to a fully randomized, balanced treatment plan. Acrivastine significantly (P less than 0.002) reduced the flare response induced by 0.4 micrograms histamine challenge 15 min after oral acrivastine dosing when compared with placebo. A significant (P less than 0.001) reduction of the weal response was noted at 25 min, although trends in this direction were already present at earlier time points.

The effect of povidone-iodine paint on fungal infection.

Povidone-Iodine (Betadine) Paint was used in thirteen patients with a proven fungal infection. Ten patients had pityriasis versicolor, two had trichophyton rubrum and one M. canis. In the pityriasis versicolor group, seven out of the ten patients were either improved or cleared up completely within 7 days. There were no adverse reactions in this group of patients and the material proved quite acceptable to them. Scanning electron micrographs were carried out on three of the patients and demonstrated the decrease in fungal elements after treatment and clinical improvement.

A comparison of acrivastine versus clemastine and placebo in the treatment of patients with chronic idiopathic urticaria.

Twenty patients of mean age 41.3 years, with a diagnosis of chronic idiopathic urticaria were assessed in a fully randomized, double-blind, crossover study to investigate the efficacy of acrivastine at two doses (8 mg and 4 mg) versus 1 mg clemastine and placebo, given three times per day. All active preparations were found to be effective, and significantly better than placebo, in controlling the signs and symptoms of urticaria. There was a higher incidence of sedation with clemastine than with either acrivastine or placebo, although this difference did not achieve statistical significance in this small study.

CAMPATH-1H in rheumatoid arthritis--an intravenous dose-ranging study.

Forty-one patients with active and refractory rheumatoid arthritis(RA) received a total of 100, 250 or 400 mg of CAMPATH-1H (CAMPATH is a trademark of Glaxo-Wellcome group companies, registered in the US Patent and Trademark Office) over 5 or 10 days in an open, uncontrolled study. Following therapy, patients were monitored for adverse effects and disease activity for 6 months. Therapy was associated with prolonged peripheral blood lymphopenia in all dosing cohorts. During the month immediately following therapy, lymphopenia was most profound in the 400 mg cohorts. The first dose of monoclonal antibody (Mab) was associated with a 'flu'-like syndrome, more pronounced at higher initial doses. One patient developed haemolytic-uraemic syndrome. There were a number of dose-related infections during the early post-treatment period and one fatal opportunistic infection which followed additional immunosuppressive therapy. Antiglobulin responses developed in 9 of 31 patients tested. The majority of patients showed symptomatic improvement following therapy and 20% of patients maintained a 50% Paulus response at 6 months, all of whom were in the 250 or 400 mg cohorts. CAMPATH-1H appears to be an effective treatment for RA. Allowing for the small number of patients treated, infections were more common with higher doses, although this was not true for adverse events overall, and therapeutic responses were more sustained at higher dosing levels. The broad specificity of CAMPATH-1H may be appropriate for the immunotherapy of RA and future studies should aim to define a dose with an optimal therapeutic ratio.

A multicentre 12-week open study of a lipid-soluble folate antagonist, piritrexim in severe psoriasis.

An open, 12-week, multicentre study was conducted to assess the efficacy of piritrexim isethionate in the treatment of severe psoriasis. Piritrexim isethionate is a lipid-soluble dihydrofolate reductase inhibitor which cannot form polyglutamates, and may be as effective as methotrexate in the treatment of psoriasis. If, as is suspected, but as yet unproven, methotrexate polyglutamates are responsible for the hepatotoxicity of methotrexate, piritrexim should be less hepatotoxic, and may offer an alternative to methotrexate therapy. Fifty-five patients were enrolled, of whom 41 completed the study. Patients were allocated to receive either 150, 225, 300, or 450 mg of piritrexim weekly, in divided doses over 72 h (low-dose groups, 150 and 225 mg), or over 36 h (300 and 450 mg groups). Twenty-four of the 41 patients who completed the study had a greater than 50% improvement in the severity of their psoriasis, as demonstrated by a reduction in the Psoriasis Severity Score, a measure analogous to the PASI scoring system. Adverse events were common, but mild, and were controlled by dose reduction. Piritrexim appears to be an effective therapy for severe psoriasis at doses of 300 and 450 mg weekly, in three divided doses over 36 h.

CAMPATH-1H, a humanized monoclonal antibody, in refractory rheumatoid arthritis. An intravenous dose-escalation study.

OBJECTIVE: To evaluate the biologic response, tolerability, and potential clinical effect of a humanized antilymphocyte monoclonal antibody, CAMPATH-1H, in patients with rheumatoid arthritis (RA). METHODS: Forty adult patients with active, refractory RA were treated with CAMPATH-1H, given intravenously, in a multicenter, open, single-dose-escalation study. Patients were assigned to dose groups of 1, 3, 10, 30, 60, and 100 mg CAMPATH-1H. RESULTS: There was a profound, immediate, and sustained reduction of the peripheral lymphocyte count; the most susceptible were the levels of CD4+ and CD8+ cells, which remained depressed during the study period. Sixty-three percent of patients developed antibodies to CAMPATH-1H. Side effects occurred frequently throughout the first 24 hours following infusion, and included fever, headache, nausea, vomiting, and hypotension. All of the immediate drug toxicities resolved within the initial 24-hour postdosing period. One patient developed a reactivation of Mycobacterium xenopi infection 10 weeks following infusion. Sixty-five percent of patients developed a clinical response; the mean duration of response was 2 weeks. CONCLUSION: CAMPATH-1H is a lymphocyte-depleting antibody that is biologically potent even after single-dose therapy. There was no correlation between biologic effect and clinical response. Sustained lymphocyte suppression was observed. Acute infusion toxicities were observed in most patients. The role of depleting monoclonal antibodies in the treatment of RA should be reevaluated.