To obtain a drug composition capable of inhibiting serine protease by formulating a compound comprising silicon.

This composition contains a compound of the formula [R1 and R2 are each H or an alkyl; R3 is hydroxyl, an alkoxy or an alkyl; R4 and R5 are each H, hydroxyl, an alkyl or a carboxylic acid functional group; R6 and R7 are each an alkoxy; (n)≥0 and (n)≤4; 3≤(m) and (m)>0] in combination with a suitable vehicle. The composition has a solid form, and is administered by oral, transrectal or topical administration. The composition is useful for treating especially bone and joint disease such as arthritis, osteoporosis, progressive polyarthritis and osteitis deformans, and dermatosis such as eczema.