BETHESDA, Md—The National Institute of Allergy and Infectious Diseases (NIAID) has formed four public-private partnerships aimed at accelerating the development of promising HIV/AIDS vaccines.

In announcing the signing of the four contracts, NIAID said it has committed about $70 million over the next 5 years to help support the research.

The program, called HVDDT (HIV Vaccine Design and Development Teams), is designed to tap the diverse research talents of industry and academia, and provide incentives to move candidate vaccines out of the laboratory and into human testing.

“Many vaccines in use today resulted from both government-sponsored and private research,” said Anthony S. Fauci, MD, director of NIAID. “The HVDDT program is a unique addition to this model that encourages the private sector to increase their AIDS vaccine efforts while allowing NIAID to work closely with its partners throughout the development process.”

Designing and testing vaccines for diseases like AIDS is an expensive and scientifically complex undertaking with no guarantees of success and little likelihood of significant profit, the NIAID said in a news release announcing the program.

‘Priming the Pump’

“The HVDDT program encourages pharmaceutical companies to invest more in AIDS vaccine research by partially offsetting their financial risk,” said Peggy Johnston, PhD, the institute’s assistant director for AIDS vaccines. “In essence, HVDDT contracts ‘prime the pump’ to get the vaccine-production engine running, including vaccine candidates for HIV subtypes that circulate in developing countries.”

HVDDT awards are incentive-based contracts aimed at vaccine candidates in the middle of the development pipeline—those not yet in clinical testing. Applicants were required to describe a clear development plan, including timelines to indicate when different phases would be completed. Funding will be provided in increments as these preset milestones are reached.

“This goal-based incentive structure helps ensure continuous progress toward a testable vaccine while at the same time rewarding companies for research accomplishments made along the way,” Dr. Johnston said.

Each of the initial HVDDT contracts proposes using a DNA-based HIV vaccine for the initial immunization. The proposals differ in the unique properties of the DNA, the specific immune response that is targeted, the delivery system used, and the manner of boosting the initial vaccine.

Each of the proposed vaccines contains the genetic information to make specific HIV proteins, either from the outer viral envelope or the internal viral core, to induce an immune response. The vaccines do not contain enough genetic information to construct a complete virus and therefore will pose no threat of HIV infection to study participants.

The Four Contracts

The HVDDT contracts went to:

• Advanced BioScience Laboratories, Inc., (ABL) Kensington, Md. The company will work with University of Massachusetts Medical School researchers to develop and test a DNA vaccine containing genes for envelope proteins from HIV strains isolated around the world.

Study participants will receive non-DNA booster vaccines consisting of recombinant HIV proteins. The researchers will explore ways to enhance the antibody response to this vaccine. Principal investigator is Phillip Markham, PhD. ABL is an affiliate of Organon Teknika Corporation, Durham, NC.

• Chiron Corp., Emeryville, California. Chiron investigators will seek to produce a vaccine against an HIV subtype commonly found in the United States called clade B, and another against clade C, the most common subtype found in sub-Saharan Africa and India.

The vaccines include the HIV envelope and core protein genes, and are intended to stimulate antibodies against the virus as well as T cells to attack virus-infected cells. The DNA vaccine will be followed by a booster vaccine consisting of alphavirus particles that deliver a recombinant HIV protein to certain immune cells.

By slightly changing the genetic code of the vaccine’s DNA, Chiron scientists hope to improve the ability of the body to decode the genetic instructions once the vaccine is administered. Principal investigator is Susan Barnett, PhD.

• University of New South Wales, Australia. David Cooper, MD, will lead a consortium of Australian universities and research organizations in the development of a DNA vaccine containing HIV genes and specific stretches of DNA that directly stimulate immune responses. The vaccination boost will contain HIV genes in a viral (fowlpox) delivery system that also includes immunity-enhancing genes.

The vaccine is designed to stimulate both antibody and T-cell responses, and to generate active immunity at mucosal surfaces, the first site of viral assault during most HIV infections.

• Wyeth Lederle Vaccines and Nutrition, Pearl River, NY. Wyeth Lederle researchers will work in collaboration with scientists at the University of Pennsylvania and Duke University to produce a DNA vaccine that contains HIV genes and genes that stimulate the immune system. The initial DNA vaccination will be boosted by a candidate vaccine consisting of multiple protein fragments, or peptides, that trigger anti-HIV responses.

The goal of this approach is to produce a vaccine that stimulates HIV-specific immune responses in very diverse human populations. The team is led by Wyeth Lederle’s John Eldridge, PhD.