Preliminary clinical data of doxycycline in LAM In a preliminary open label study of doxycycline (50 - 100 mg qds) in 10 patients with LAM, doxycycline improved 6 minute walk distance) and Borg dyspnoea score (Glassberg et al. Data presented at the LAM Foundation International Research Conference, Cincinnati Ohio 2006). In a single case report, Moses et al. observed an improvement in FEV1 and oxygenation during exercise in a patient with LAM treated with 100mg doxycycline daily (Moses, Harper et al. 2006). In both of these cases MMP-2 and -9 were initially present in the patient's urine and was undetectable after treatment with doxycycline. In a study of 14 patients, doxycycline 100mg bd is known to give a mean plasma concentration of 4.41 µg/ml (range 1.9-9.4 µg/ml)(Prall, Longo et al. 2002).