LONDON Drug delivery specialist Cortecs plc, of London, last week released results from the analysis of bone mineral density after one year in the Phase III trial of Macritonin, an oral formulation of calcitonin for the treatment of osteoporosis. According to the company, the data indicate that Macritonin ¿has at least qualitative action¿ on bone mineral density, and this effect is dose-related. The findings are consistent with the three-month and six-month biochemical bone marker data.

Michael Flynn, CEO, commented, ¿The bone mineral density results are as we had expected, and although only qualitative, are very reassuring. Our early trials on bone resorption markers had suggested that 400 I.U. of Macritonin is the optimal dose. Although only qualitative so far, our interpretation is that there is an indication from the bone mineral density data at this time point that 800 I.U. is in the lead.¿

The Phase III European trial is due to run for two years, with the aim of showing equivalence with nasally administered calcitonin.

Cortecs submitted marketing authorization applications for Macritonin in the last quarter of 1997 in the seven European countries where nasal calcitonin is registered. The applications were based on biochemical bone turnover markers. However, the first country to assess the application, Finland, has refused approval on the basis of bone marker data, and asked to see clinical data on bone mineral density.

¿The response from Finland is not unexpected,¿ Flynn said. ¿We expect some authorities will require bone mineral density for registration and others will accept bone destruction markers as evidence of similar efficacy to the registered product, nasal calcitonin.¿

The one-year analysis of bone mineral density was made to assist in planning the U.S. Phase III trial. On this basis, Cortecs intends to recruit approximately 200 patients to each arm. ¿It is reassuring that the proposed trial in the U.S. is of a manageable size and is comparable with the scale of similar trials with anti-resorptive agents,¿ Flynn said.