Serratiopeptidase

Serratiopeptidase (Serratia E-15 protease, also known as serralysin, serrapeptase, serratiapeptase, serratia peptidase, serratio peptidase, or serrapeptidase), is a proteolytic enzyme (protease) produced by non-pathogenic enterobacterium "Serratia" sp. E-15, now known as "Serratia marcescens" ATCC 21074. This microorganism was originally isolated in the late 1960s from silkworm "Bombyx mori" L. (intestine), Serratiopeptidase is present in the silkworm intestine and allows the emerging moth to dissolve its cocoon. Serratiopeptase is produced by purification from culture of Serratia E-15 bacteria. It is a member of the Peptitase M10B (Matrixin) family.
Health claims.
Some alternative medicine proponents claim that serratiopeptidase is beneficial for pain and inflammation but "existing trials [have been] small and generally of poor methodological quality." Online medical journal "Bandolier" (specializing in evidence-based thinking about healthcare) published an article (in about 2001) in response to a reader's enquiry about serratiopeptidase. After searching PubMed and the Cochrane Library "to see if there are any randomised, controlled trials", the article stated that the "evidence on serratiopeptidase being effective for anything is not based on a firm foundation of clinical trials."
The search found 34 publications in the medical databases covered, that addressed the efficacy of serratiopeptidase, of which several were found to be animal experiments, personal letters, uncontrolled trials or those with inadequate or nonexistent randomisation. The article warned against ignoring safety issues with use of biological agents. No studies were found to have been conducted on the efficacy of serratiopeptidase as treatment for back pain, heart attack, stroke, or asthma. Of the 10 medical conditions with randomized-evidence studies on file in connection with serratiopeptidase, the quality or construction of the trial studies was described as "generally poor".
In a news article published Feb 22, 2011, Kyodo News reports: 
Following that, the Health Science Authority in Singapore had conducted a re-evaluation of the risk benefit of serratiopeptidase for its approved clinical uses. They concluded that "there is no substantive scientific evidence to support the classification of serratiopeptidase as a medicinal product" and decided to phase out serratiopeptidase-containing preparations as medical products.
In a case report it was seen that serratiopeptidase may cause lysis of fibrin wall around an abscess and cause its local spread. So its use sometimes could be harmful in treating abscess.