FAQ

ImmunoScience, Inc.

Frequently Asked Questions –Contre Vir™

What is a Vaccine?

A vaccine is a substance introduced into the body to build-up immunity against an invading germ like bacteria or viruses.

How do Vaccines work?

Vaccines work by either stimulating production of antibodies against the invading micro-organism or by stimulating production of certain special “military” cells called CTL (Cytotoxic T Lymphocytes) that search and destroy body-cells that contain the invading organism, or by a combination of both of the actions. The first method is useful primarily against bacteria and the second primarily against viruses.

What is a “Therapeutic” Vaccine?

A therapeutic vaccine is one that is given to a patient AFTER being exposed to an invading micro-organism. This is in contrast to a “prophylactic” vaccine which is given to prevent the micro-organism from invading in the first place. A therapeutic vaccine is currently used only for the treatment of rabies. Therapeutic vaccines are useful only when the incubation period (the time between being infected and the onset of symptoms) of the illness is long enough that defense mechanisms can be established before death occurs. In rabies, the incubation period is 60 days to 1 year and in HIV it is 10 or more years allowing enough time for the immune system to be strengthened by the vaccine before death. This “therapeutic” use is different from a common preventive use of vaccines such as childhood immunizations against diphtheria or whooping cough or measles.

What is a Live Vaccine?

A live vaccine contains a weakened version of a live micro-organism (bacteria or virus) that one desires to build-up protective immunity against. The oral vaccine against polio (Sabin) or the rabies vaccine belong to this category. Other vaccines use only a portion of the invading micro-organism’s proteins or dead micro-organisms as in the Salk vaccine. Live vaccines build-up “military cells” (CTL) that go on search and destroy missions killing the invading micro-organisms. Dead vaccines usually only produce antibodies against the invading micro-organism but are unable to form “military cells”. Your body is capable of making antibodies against a portion of a foreign virus or bacterium without actually being infected.

What is a Recombinant Vaccine?

A recombinant vaccine is created by genetically altering the invading virus to modify and thus weaken it so that it will boost immunity without causing death and disease. In the case of HIV, the vaccine contains everything from a live HIV strain except the nef gene. Previously, other methods were used to make vaccines in which the micro-organisms were weakened by methods such as heat, radiation and chemicals. These methods are not useful in making a live anti-HIV vaccine because the virus is extremely fragile and dies when conventional weakening methods are used.

Do other vaccines work by forming “Military Cells” (CTLs)?

Yes. All the live virus vaccines such as Small Pox, Rabies, Rubella, Measles and Polio work by making specific “military cells” that search, identify and destroy any invading virus-bearing cells and thus not allowing the infection to take hold or eliminate if it is established. Contre-VirÔ is not at all unique from the perspective of how these vaccines work.

Why do HIV sufferers die?

HIV sufferers die because the virus grows relentlessly; killing a system that is essential for survival. Since it attacks the immune system, the patients die from a variety of other infections to which they are rendered defenseless.

Why doesn’t the body fight back against HIV infection?

The body tries. Most patients have very high levels of circulating antibodies against HIV. However, these antibodies don’t do much good because the virus is hidden inside cells where the antibodies cannot reach. What fails in HIV infection is a concerted attack of “military cells” (CTLs) against any cell harboring HIV. In order to have such a strong attack, the infected cells need to send a minimum of TWO signals to the “military cells”. One signal is appearance of foreign proteins on the surface of the invaded cell that are recognized by specific “military cells” to attack. The second signal is a specific chemical signal sent by means of certain specific chemicals some of which are called “lymphokines”. A protein generated by HIV called “Nef” has been shown to prevent a specific modification in the first signal AND interfere with several lymphokines required for the second signal. Thus, HIV blocks the signaling successfully and renders the “military cells” ineffective. This blocking or cloaking mechanism is contained on a specific gene of the HIV called nef which produces the Nef protein..

How is Contre-VirÔ Vaccine Made?

Contre-VirÔ is made by genetically engineering this cloaking or blocking gene nef out of the HIV and thus making a new virus. This creates a version of the virus that is unable to stop production , recruitment and attack of the “military cells” (CTLs) and thus cannot harm the human in a similar way as a heat-treated or radiation treated live virus vaccine would.

How does Contre-VirÔ work?

Contre-VirÔ, which is essentially live HIV viruses weakened by removal of their nef gene, is administered to a patient suffering from HIV infection. It invades the patient’s body just as any other HIV would. However, unlike the real HIV, Contre-VirÔ does not interfere with production, recruitment and attack of “military cells”. The “military cells” will now do their designated job and start “search and destroy” missions throughout the body to kill any cell harboring HIV. Since there is no difference between Contre-VirÔ and the “real” HIV in terms of the proteins seen on the surface of the cell, activated “military cells” cannot tell the difference between cells containing Contre-VirÔ and cells containing the “real” HIV, thus killing them all. Why and how does this happen? It’s a situation where similarities and dissimilarities are used to best advantage. The dissimilarity between the two viruses allows the “military cells” to function properly whereas the similarity makes both of them identifiable to the “military cells” without cloaking.

What is involved in the treatment?

The current protocol consists of two injections of Contre-VirÔ- a month apart. Further research may require modification of this protocol.

How long does it take to show benefit?

Most patients are expected to show substantial improvement in their immune system within 14-16 weeks after the first injection. This period will be better defined after the first larger scale clinical trial.

Is this a “cure”?

The Company believes - Yes. Since the “military cells” have a long memory, and access to every part of the body, it is postulated that they will destroy every cell harboring HIV in a finite period of time, eliminating the virus completely from the body.

Will the patients still remain HIV positive?

Yes. Since testing for HIV involves detection of antibodies, these patients will be ‘HIV Positve” even though they are disease free. This is similar to one having antibodies to a strep infection long after it is cured by antibiotics.

How long will it take to “cure” an HIV infected patient?

The results may vary, however, it is estimated that within 18-24 months after the first injection, HIV shall be eliminated from the body. This period will be better defined after the first larger scale clinical trial.

Can the treated patients be infected with HIV again?

No. The immunity created by Contre-VirÔ is expected to be life-long and no repeat infection is likely from all the known sub-types of the HIV virus.

Will Contre-VirÔ be made ineffective by mutations of the HIV?

The proteins that the “military” cells see on the surface of the infected cells are from a “conserved” i.e., non-changing part of the virus called Gag proteins. Since these proteins do not change frequently like the Env proteins, Contre-VirÔ should maintain its effectiveness infinitely and across almost the entire spectrum of mutant strains.

How is Contre-VirÔ different from Protease inhibitors and other drugs?

The drugs used in the treatment of HIV do not kill the “blue-prints” of HIV (pro-viral DNA). They only stop production of the virus from these “blue-prints”. Given over a period of time, the cells containing the “blue-prints” die and are replaced with healthy cells. For example, the blood cells , mucosal and lymphoid cells are replaced in about a year and eliminate the virus “blue-prints” harboring within them. HOWEVER, the “blue-prints” also exist in some brain cells called “glia” and these cells are in the body for life. They do not die out. These “blue-prints” present in the brain are fully capable of generating large quantities of the virus and re-invading the whole body as soon as the drugs are stopped or as soon as the virus becomes resistant to the effect of the drugs.

Can a patient still infect others while receiving Contre-VirÔ?

Once HIV has been eliminated from the body, the patients will not be able to infect others. However, during early stages of treatment, they will be able to transmit HIV.

Will there be any side effects?

Research is still not complete. However, it is not likely that introduction of additional HIV in one already infected will pose any substantial danger and potential for side-effects. The patients in the pilot study reported no side effects.

Can Contre-VirÔ be used as a preventive vaccine?

Yes. Contre-VirÔ can indeed be used as a “prophylactic” vaccine to immunize the body before the infection. However, since HIV can be more easily prevented by avoiding high-risk behavior known to be associated with the transmission of HIV, abstaining from such behavior continues to be the best means of prevention. Contre-Vir™ will certainly have application as a prophylactic vaccine for high-risk individuals such as medical workers, chronic recipients of blood products and for commercial sex workers or habitual IV drug abusers.

Is Contre-VirÔ patented?

Patent applications were made with a priority date of December 24, 1994 and are being actively pursued in the United States, Canada, Japan, Brazil, all countries in Europe and several more countries. On July 7, 2000, an Australian patent was granted. The US patent is expected to be granted soon.

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