Two Regimens Deliver High Sputum Conversion Rates in M. Xenopi Pulmonary Infection

Jun 23, 2024

Photo Credit: Inkoly

Two treatment regimens showed higher conversion rates for patients with Mycobacterium xenopi pulmonary infection, and how this improves future mortality rates.

CaMoMy, the first clinical study to evaluate the 6-month sputum conversion rate in patients with Mycobacterium xenopi pulmonary infection demonstrated a high conversion rate for two treatment regimens, consisting of ethambutol, rifampicin, and either clarithromycin or moxifloxacin.

“Individuals who have a pulmonary infection with Mycobacterium xenopi have a poor prognosis, with a 5-year mortality rate of 69%¹,” expressed Prof. Claire Andrejak from CHU Amiens, in France. “It occurs mainly in patients with chronic respiratory disease. Unfortunately, the optimal treatment is unknown.” The phase 3 CaMoMy trial (NCT01298336) included patients with M. xenopi pulmonary infection (n=92), randomly assigned to a regimen of ethambutol plus rifampicin plus clarithromycin or to a regimen of ethambutol plus rifampicin plus moxifloxacin. The primary objective was determining the 6-month sputum conversion rate.

In the overall population, the 6-month sputum conversion rate was 93.2%. “Next to this, we observed clinical improvements after 6 months, with an anorexia rate of 19.2% versus 28% at baseline, a weight loss rate of 15.4% versus 48.3% at baseline, and a fatigue rate of 34.6% versus 58.5% at inclusion,” said Prof. Andrejak.

There was no difference between the two treatment regimens concerning the 6-month sputum conversion rate, fatigue rate, weight loss, or anorexia rate. Severe AEs were documented in 18.6% of the participants in the clarithromycin arm and 20.0% of those in the moxifloxacin arm. “These events were mostly related to the use of ethambutol,” explained Prof. Andrejak.

“We saw a high 6-month sputum conversion rate for two treatment regimens in our severely sick patient population, with the majority of patients having the cavitary form and a positive smear,” decided Prof. Andrejak.

Medical writing support was provided by Robert van den Heuvel.