This open phase IV multicentre trial was carried out to evaluate the efficacy and tolerability of amtolmethin guacyl in patients with acute osteoarthritis in at least one of the following locations: knee, hip, vertebral column. Amtolmethin guacyl is a drug belonging to the NSAID class whose action is comparable to that of other active ingredients belonging to the same class, but it is particularly interesting that a low incidence of collateral effects involving the gastric mucosa, equal to around 5%, has been reported in all clinical trials. It has been demonstrated that amtolmethin guacyl provokes an increased production of nitric oxide (NO), an important mediator of the gastric mucosa defence system through the induction of the nitric oxide synthetase (NOS) enzyme.
A total of 41 centres took part in the trial and an overall population of 388 patients were recruited. The protocol specified that the drug should be taken for one month at a dose of 1200 mg/die (2 tablets b.i.d.) for 3 days and 600 mg/die (1 tablet) for the remaining 27 days. At screening, after 7 days (T1) and at the end of treatment (T2), the parameters of efficacy were evaluated using a semiquantitative scale for the following symptoms: spontaneous pain and pain on movement, joint function and swelling. All patients were asked to keep a daily diary to evaluate gastric tolerability, whereas overall tolerability was evaluated by recording adverse effects and determining the common laboratory parameters. The statistical analysis was calculated both according to intention to treat (379 patients) and by protocol (372 patients), using Friedman's test to analyse the 4 scales of signs and symptoms (basal visit vs T1 vs T2).
A statistically significant difference (p<0.01) was found in both analyses for all 4 parameters examined between the basal evaluation and the two evaluations during and post-treatment.
The analysis of vital parameters, laboratory parameters and adverse effects confirmed the good tolerability of the product.