inactivation of the AIDS virus by heat treatment by 1985 (Hammes 1995; Leahy 1995; McAuley 1995; Persky 1995).
Heat-treated AHF became available in 1983 (Persky pers. com. 1995), and by 1985 heat treatment was accepted as effective in deactivating HIV (McDougal, et al. 1985). Even though there was a reasonable supply of heat-treated products, the FDA waited until 1989 to require the recall of all untreated AHF concentrate. By the time the FDA required recall of untreated units of AHF, the manufacturers had acted on their own (Epstein interview).
In this case, it is possible to construct a scenario in which the legal authority hypothesis cannot be so easily rejected. This may seem a strange conclusion given the argument above that the FDA might, in July 1983, have delicensed all AHF concentrate. However, the data necessary to delicense only untreated AHF concentrate, while leaving heat-treated AHF concentrate on the market, were not necessarily available for HIV. Removal of all AHF concentrate from the market might have been premised on a determination that, given the epidemiological evidence that was accumulating, AHF concentrate could no longer be determined to be safe under normal conditions of use. However, circa 1983, that same conclusion would have to be drawn with respect to heat-treated AHF concentrate as well. There was no test that would demonstrate definitively that heat-treated AHF concentrate was less infective with respect to HIV than non-heat-treated AHF concentrate until the mid-1984 studies by the CDC (CDC, MMWR, October 1984; McDougal, et. al. 1985). The CDC, in cooperation with Cutter Biological, conducted a study in which the AIDS virus was added to Factor VIII concentrate and was subsequently heat treated. The study showed that the virus was undetectable after 24 hours of heat treatment (CDC, MMWR, October 1984). Preliminary data were presented to NHF's Medical and Scientific Advisory Council in September 1984 and formed the scientific basis for NHF's subsequent October 1984 recommendations that heat-treated AHF concentrate be considered in the treatment of hemophilia.
On the other hand, the FDA could have decided that untreated AHF should be removed from the market because heat-treated AHF concentrate was safer with respect to the propagation of hepatitis. However, as is explained in Chapter 4, the FDA and others for many years had doubts about the utility of heat-treating AHF concentrate for hepatitis. Recipients of AHF concentrate were likely to be infected with hepatitis from exposure to numerous donors through multiple administrations of AHF concentrate (Aledort, Dietrich, Levine, Lusher interviews). This position itself may not have been well considered, but that seems to be the way that the FDA and others looked at the situation as of the end of 1983 (Aledort, Dietrich, Levine, Lusher interviews).