Abstract
Lymphangioleiomyomatosis (LAM) is characterised by lung cysts and airflow obstruction. Matrix metalloproteinases (MMPs) have been implicated in lung destruction in LAM. We performed a randomised, double blind trial, comparing the MMP inhibitor doxycycline with placebo on the progression of LAM.
Twenty three females with LAM were randomised to doxycycline 100 mg daily for three months followed by 200 mg daily for 21 months, or matched placebo. Lung function, exercise capacity, quality of life and MMP levels were measured.
Twenty one patients completed 6 months treatment, 17 completed 1 year and 15 completed 2 years. Four withdrew due to pneumothorax and four for other reasons. Mean decline in FEV1, the primary endpoint, did not differ between the groups being −90 (SD 154) mL/year in the placebo group and −123 (246) mL/year in the doxycycline group (difference −32.5, 95% C.I. −213 to 148, p=0.35). Doxycycline had no effect upon vital capacity, gas transfer, shuttle walk distance or quality of life. Urine MMP-9 measurements were lower with doxycycline treatment (p=0.03).
Although with limited numbers we cannot completely exclude an effect of doxycycline, the lack of effect on any outcome makes it unlikely that doxycycline has a useful effect in LAM.
- ERS