Many biological medicines draw safety warnings - researchers

About a quarter of biological medicines approved in the US and Europe since 1995 have triggered safety warnings in the years after entering the market, according to Dutch researchers.

Immune system disorders, infusion reactions, infections and cancer concerns were among the reasons for safety warnings for biological medicines, which are made with proteins derived from living cells rather than the chemicals used in typical drugs.

These medicines, called biologics or biologicals, are typically injected and treat a range of conditions including anemia, rheumatoid arthritis, hepatitis and cancer.

Thijs Giezen of Utrecht University in the Netherlands and colleagues tracked safety-related regulatory actions involving 174 biological medicines approved in the US or the EU between January 1995 and June last year.

Some biologics, including vaccines, were excluded.

As of June, regulatory actions were taken involving 41 of the medicines, or 24 per cent of the total, the researchers wrote in the Journal of the American Medical Association.

Such safety-related actions typically involve a company placing a warning on a drug's prescribing instructions describing potential harm from using it. Sometimes warnings reduce a drug's sales.

Chemical-based drugs also periodically draw safety warnings from regulators but there is no recent similar data to compare the rates, the researchers said.

The average time for a safety-related regulatory action was about three-and-a-half years after approval, and 71 per cent occurred within five years of approval, the researchers said.

Biologics are an important and growing part of today's medicine. Between 2003 and 2006, they represented almost a quarter of the drugs approved by US and EU regulatory authorities, the researchers said.

Examples of drugs that drew safety warnings include Genentech Inc.'s cancer drug Herceptin due to a heart inflammation called cardiomyopathy and lung problems.

Also, Schering-Plough Corp.'s arthritis treatment Remicade carries a warning due to increased risk of infections and rare cases of a type of lymphoma. And ImClone Systems Inc's cancer drug Erbitux carries a warning due to serious and sometimes fatal reactions in about three per cent of patients.

Just last week, the US Food and Drug Administration ordered strong black-box warnings for Genentech's psoriasis drug Raptiva, saying patients given the once-weekly injections are at risk for life-threatening infections.

The FDA said the new warnings will alert doctors and patients to the risk of a rare brain infection called progressive multifocal leukoencephalopathy and other serious infections.