Two priming immunizations of the GeoVax DNA vaccine, followed by a single booster vaccination of the MVA vaccine, were 96% effective in protecting non human primates against developing clinical AIDS for over 40+ months following challenge with a virulent AIDS causing HIV-1 virus. The vaccine controlled the challenge infection to the very low levels of virus characteristic of long term, naturally HIV-1 infected humans who do not develop clinical signs of AIDS (long-term non-progressors). In contrast to the GeoVax immunization regime, competitor vaccines are administered in as many as 5 or more doses; which is impractical in real-world applications.
Twenty two out of 23 (96%) non-human primates receiving GeoVax vaccine were protected against developing clinical signs of AIDS. The 1 of 23 that was not protected received only a partial dose of vaccine. Over 83% of the unvaccinated controls (5/6) died of clinical AIDS within 8 months post-virus challenge, and each had levels of virus in the blood stream 10 to 100 fold higher than in typical HIV-1 infected humans.
The "Duration of Protection" against clinical signs of AIDS raised by the multi-protein vaccine continued for the duration of the experiment - 200 weeks - demonstrating excellent long-term protection. To our knowledge, no other HIV vaccine or large size vaccination/challenge trial has reported such a high level of protection for such a long period of time. The trial was concluded at 40 months post AIDS virus challenge so the final duration of protection is unknown.
GeoVax's vaccine effectively stimulated development of a "memory response" capable of protecting long after immunization. Vaccinated monkeys were challenged with pathogenic virus 7 months after vaccination and still exhibited excellent virus and disease control.