The U.S. Food and Drug Administration's approval process for medications or injectable devices is long and arduous, with criteria much more stringent than in other countries. Rigorous toxicology tests must be passed before human trials begin, and those trials often take months to years'and a lot of money'to complete. As a physician who participates in FDA clinical trials, I agree that the process can be long and frustrating. But it ensures the safety and effectiveness of U.S. medical treatments.
A reader wrote to HIV Plus in the October issue about a treatment for facial lipoatrophy that he had obtained in Mexico. Bio-Alcamid (polyalkylimide) or injectable silicone is a synthetic polymer developed and produced outside the United States as a permanent injectable agent for soft tissue augmentation. It is not FDA-approved for any use and there are no reports in peer-reviewed medical journals supporting its safety or effectiveness in treating HIV-related facial lipoatrophy, although patient reports suggest it may be useful.
Bio-Alcamid is closely related to other synthetic injectable fillers containing polyacrylamide (Formacryl, Bioformacryl). Formacryl has been associated with cases of late-appearing infection, and impurities in polyacrylamide-containing products may be toxic to the nerves, kidneys, and other organs. There is no good science supporting the claim that these substances can be easily and completely removed if problems arise. Any injectable permanent synthetic filler, including Bio-Alcamid, also carries the potential for such side effects as migration, toxicity, the formation of lumps and nodules, pigment change, and infection that may not become apparent for months to years. It is unclear if HIV infection may predispose patients to greater risk.
Bio-Alcamid is too new to conclusively pass judgment on its long-term effects. Serious and respectable long-term scientific study by qualified physicians may ultimately prove its safety and usefulness for HIV facial lipoatrophy. I welcome legitimate efforts toward this end, although such studies will be expensive and will take time.
I would like to correct the perception that 'Bio-Alcamid is safer than silicone,' as the HIV Plus reader wrote. There is no evidence to support this claim. In the 1970s and 1980s liquid injectable silicone was used to treat 201 patients in FDA-approved studies for facial fat loss not associated with HIV. Long-term results suggest that purified 'injectable grade' liquid silicone, when appropriately injected in small volumes over several treatments, is very safe and effective. In 2000 a report by the National Academy of Sciences absolved silicone of a relationship to systemic disease. To date, liquid injectable silicone (SilSkin), when used off-label by trained physicians, is the only injectable filler in the United States that is legal, permanent, safe, and cost-effective for the treatment of HIV-related facial lipoatrophy. It also is the only agent to have passed toxicology testing required by the FDA and to have entered human trials for treatment of this condition.
My colleagues and I reported in the journal Dermatologic Surgery of our success over four years in treating 350 facial lipoatrophy patients with highly purified injectable silicone. Patient satisfaction was very high, and there were no adverse reactions. As with any treatment, longer-term follow-up is needed to establish long-term safety and efficacy.
Any permanent treatment for HIV-related facial lipoatrophy will be considered investigational for many years to come. If you seek a more permanent treatment option for HIV facial lipoatrophy, make sure you are treated by an appropriately trained physician who employs a well-designed investigational protocol based on good science. Be aware of your physician's credentials'and of appropriate scientific data that supports the treatment you are receiving.
Jones is a board-certified dermatologist in practice in Los Angeles and a clinical assistant professor of dermatology at the University of California, Los Angeles.
