Oxatomide for stable asthma in adults and children

Oxatomide is a histamine H1-receptor antagonist. As an oral agent, oxatomide may be useful in managing asthma. Some guidelines recommend oxatomide for long-term prophylaxis of asthma in children. There is no clear evidence whether children or adults with asthma benefit from oxatomide.

To determine whether oxatomide alone, or in combination with other interventions, results in better disease control in people with asthma.

The Collaborative Airway Group register and Collaborations trial register CENTRAL were searched using terms: oxatomide* OR Celtect OR Pinset OR KW-4354 OR Tincet. Reference lists of all relevant trials or review articles were checked. Enquiries were made of authors of included studies and relevant pharmaceutical companies. A search of 'Igaku Chuo Zasshi' and 'J-Medicine' were made using the following terms: oxatomide (also in Japanese) or Celtect (also in Japanese) or KW-4354.

Studies were randomised, placebo-controlled trials and the interventions were oxatomide or matched placebo given alone or in combination with other asthma-medication for at least 4 weeks.

Four independent reviewers performed assessments of methodological quality and extracted relevant data.

Six studies are included in this review. Three studies were mainly conducted in adults, two were conducted in older children (5-16 years) and one in infants (18-25 months). Trial duration was 4 to 52 weeks. Doses of oxatomide varied between studies, ranging from 1 mg/kg/day for infants to 180 mg/day for adults. Only data on adverse events was suitable for meta-analysis. Although PEF did not change significantly in any of the studies, the FVC and FEV1 improved significantly in two. There was no uniform change in symptom scores. There was no significant difference between oxatomide and placebo treatment in use of inhaled corticosteroid or bronchodilator. Two studies showed significant improvement with oxatomide as judged subjectively by physicians. Adverse events, analysed using data from 4 parallel and one cross over study, showed oxatomide to be associated with a significantly higher risk of any adverse event (OR: 2.97, 95%CI: 1.69 to 5.22) and drowsiness (OR: 5.22,95%CI: 2.53 to 10.74).

There is no evidence to show that oxatomide has a significant effect on the control of stable asthma. Some studies reported significant benefits in subjective parameters. There was improvement in some lung function outcomes reported, but this were not consistent across measures or studies and may represent reporting bias. Adverse events, including drowsiness, were significantly greater with oxatomide than placebo.