On July 17, a high-ranking official at the U.S. National Institutes of Health (NIH) pulled the plug on a hotly anticipated clinical trial for a government-funded vaccine to combat human immunodeficiency virus (HIV), the bug that causes full-blown AIDS. The announcement by Anthony Fauci, director of the NIH's National Institute of Allergy and Infectious Diseases (NIAID), was the latest in a series of setbacks in the search for a vaccine the world has been anxiously awaiting for more than two decades.

Fauci's reason for canceling the trial: There is not enough evidence that it's effective to justify a wide-reaching trial.

Vaccines come in two forms: protective and therapeutic. A protective vaccine typically consists of a weakened form of a virus that, when injected, alerts the immune system (antigens or proteins on the virus' surface), which in turn generates antibodies (other proteins) that clobber the invaders and remain on high alert should the bug ever try to attack again. If the virus hits again, the immune system will be armed and ready, with the weapons it needs to launch a preemptive strike to wipe it out before it can infect any cells.

Therapeutic vaccines are designed to battle illnesses already in the body by helping disease-killing T cells recognize and target them. In the case of HIV, candidate vaccines typically consist of parts of the virus that furtively slipped into the body and is successfully eluding the immune system. Whereas the virus entered the body undetected, the protein does not: The T cells will view it as a dangerous invader and attack it everyplace in the body, including on the viruses, reducing and perhaps even clearing the infection completely.

Fauci said that he nixed the trial, in part, because of the failure of Merck & Company's 3,000-person STEP vaccine trials in September. In lab tests, the Merck vaccine showed that immune system cells produced signaling proteins called cytokines when they came in contact with the vaccine. Researchers believed these so-called "correlates of immunity"—essentially signs that immune system was responding to the vaccine— indicated that it would fight infection.

They were wrong: The Merck vaccine proved ineffective at preventing infection or reducing levels of the virus in an infected person's body. The government-funded vaccine, known as PAVE (Partnership for AIDS Vaccine Evaluation), is formulated similarly to Merck's vaccine, consisting of three genes found in HIV attached to a weakened form of the common cold designed to draw the attention of the immune system. Originally set to be tested on 8,500 people, PAVE's trial was downsized to 2,400 soon after the failure of the Merck vaccine.

After a NIAID-sponsored summit in March revealed that there were too many unanswered questions, Fauci decided that priorities needed to be revised.

Toward that end, has co-authored an article in Science last week that calls for more basic research and smaller studies (to prove a candidate vaccine's effectiveness) before conducting large-scale human trials. Fauci spoke with ScientificAmerican.com to discuss this new tack—and whether there's still a chance of an HIV vaccine.

5 Comments

1. 1. Mariojosé 04:33 PM 8/1/08

   Amiable readers, to maintain the fidelity we published the article in the original language.
   Las vacunas son una preparación de antígenos que se inyectan en el cuerpo y generan una respuesta de ataque por medio de los anticuerpos que contribuyen a ponerle fin a algún virus o bacteria. Una vez que han sido suministradas en el organismo generan lo que se conoce por memoria inmunológica por lo que, en la mayoría de los casos, vuelven inmune a la persona a esa enfermedad determinada.La inoculación cuenta con antecedentes en China y Turquía, pero la primera vacuna como tal fue inventada, en 1796, por un médico rural inglés llamado Edward Jenner que dio con una forma para combatir la epidemia de la viruela. Jenner, observó que las mujeres que trabajaban ordeñando las vacas contraían una enfermedad que era conocida como la viruela de las vacas, sin embargo, ésta las hacía inmunes a la viruela humana. Así, sacó una muestra de leche de vaca de la mano de una de las granjeras y la inyectó en el brazo de un niño. Éste sufrió los síntomas de la viruela vacuna. Cuarenta y ocho días después, cuando ya no quedaban rastros de la enfermedad, le inyectó una muestra de la viruela humana y éste no padeció ningún síntoma del mal. Basados en esta observación, nosotros planteamos la siguiente hipótesis: las cucarachas son los insectos sobrevivientes más antiguos sobre la faz de la tierra, por su carga atómica que poseen han podido sobrevivir a grandes cataclismos y fenómenos atmosféricos, así también, las terribles bombas atómicas creadas por el hombre.
   Existes miles de variedades de cucarachas, pero específicamente las cucarachas que viven en las alcantarillas y se alimentan de los residuos vaginales, el semen, las heces fecales y los excrementos. Estas han logrado sobrevivir, son inmunes y son portadoras del virus del sida. De igual manera como Edgard Jenner, hizo su investigación se hará es mismo procedimiento. Queremos decir hay que aumentar la capacidad inmune del cuerpo humano, aumentar los anticuerpos para poder resistir y convivir con el VIH/Sida. Cuando el cuerpo recibe esta dosis de virus o bacterias, el sistema inmunológico se pone en alerta y destruye a estos agentes que le son extraños al organismo. Así, cuando una dosis realmente dañina decide atacar, el cuerpo ya se encuentra preparado para reconocerla y atacarla rápidamente. Edward Jenner nació el 17 de mayo de 1749 en Berkeley, condado de Gloucester, Inglaterra y falleció un 26 de enero de 1823 en la propia localidad de Berkeley. Fue un afamado
   investigador, médico y poeta.

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2. 2. Mariojosé 05:09 PM 8/1/08

   Amiable Readers, the proteins of the cockroach are the solution for the vaccine of AIDS. The director of the NIAID, Dr. Anthony Fausi, must initiate the investigation.

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3. 3. jpuah23 01:31 PM 12/7/09

   There are many natural ways to rid your body of HIV. In contrast with the traditional antiviral cocktails of medicine today, which cost thousands, have severe side effects, and comes with the double edged sword delema,meaning if the virus doesn’t kill you the cocktails will, this medicine is all natural.Please visit this site for the full information about this subject……http://pushgood-nomorehiv.blogspot.com/

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4. 4. dlanasa 09:54 AM 9/20/10

   I read a testimoney that coconut milk can stop AIDS; monolaurine can be purchased as the nutrient found in the coconut milk.
   There was a doctor from India that said he stopped the AIDS virus with a mixture of spices. I read the abstract about 7 years ago; it is on medline. I vaguely remember he called the mixture with a word that begins with "K". And what about Safi sold in East Indian grocery stores. There are so many foods that support the immune system, why do they not talk too much about them?

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5. 5. dlanasa 09:57 AM 9/20/10

   I read a testimoney that someone was healed of AIDS with coconut milk; monlaurine is a nutrient from that food that can be purchased from the health food stores.
   Also, I read an abstract of a study that a doctor from India stopped the sickness with some spice mixture that began with a "K" about 7 reads ago I read it. What about Safi? Can be purchased in an East Indian grocery store. So many foods support the immune system. Why is not diet mentioned more?

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