Promising results for Vical’s HIV vaccine

The vaccine was well-tolerated and the subjects showed strong cell immunity responses that may be important for controlling HIV infection.

The trial involved priming an immune response with three doses of a plasmid DNA vaccine, based on Vical’s DNA delivery technology, and boosting the response with a single dose of adenoviral vector vaccine given at a later date.

Viral commented that the trial was another promising step toward the development of an effective HIV vaccine.

The vaccine was developed by scientists at the Dale and Betty Bumpers Vaccine Research Center of the National Institute of Allergy and Infectious Diseases (NIAID), and was manufactured by Vical.

The vaccine incorporates HIV genetic material from the three most globally important HIV subtypes, clades A, B and C, which are involved in about 85% of all HIV infections around the world.

The vaccine used in the phase I trial incorporates parts of four HIV genes. The fourth vaccine component is a modified version of the HIV gene named env. The env gene codes for a protein on the outer coat of the virus that allows it to recognize and attach to human cells. Three of these vaccine components are modified versions of HIV genes called gag, pol and nef, synthetically made based on sequence from clade B, the subtype that predominates in Europe and North America.

Vaccine Research Center scientists were the first to combine modified env from clades A and C, which are the most common in Africa and parts of Asia, with the modified env gene from clade B.