The New York Times - June 1, 1984
Harold M. Schmeck Jr.

The importance of such a vaccine, made artificially in the laboratory, is that it could be produced in virtually limitless quantity, probably at relatively low cost, and would be free from the risk of contamination by substances from human blood.

Furthermore the promise shown by the experimental vaccine against heptitis B virus also suggests that other vaccines against important human diseases may be made by gene-splicing technology in the future.

Dr. Edward M. Scolnick of the Merck Institute for Therapeutic Research, a leader in the research project, said he believed the new vaccine offered the first chance to eliminate the hepatitis B virus as a widespread cause of liver infection and probably of liver cancer throughout the world. He said it would probably take about three generations of widespread use to accomplish this and that hepatitis B virus thereafter would be only a rare cause of human disease.

A expensive, conventional vaccine against the hepatitis B virus already exists, but it is made from a virus protein that circulates in the blood of people who have been infected and is harvested from donated human blood plasma. Because of its source, it is difficult to make and is too expensive for worldwide use. It has been avoided by some people because they fear that a vaccine derived from donated blood might expose them to extraneous blood-borne viruses such as those that may cause acquired immune deficiency syndrome, AIDS.

Many promiscuous homosexuals become infected wth the hepatitis B virus. It is among this group also that AIDS is most common, hence the fear that donated blood containing the hepatitis B protein might also contain the virus or viruses that are believed to cause AIDS. However, the vaccine material is rigorously purified and fear of contamination is believed to be unfounded.

Although the vaccine is still in the research stage, Dr. Scolnick estimated that it might become generally available in two or three years. The timing cannot be predicted precisely because it depends on the outcome of future research and on approval by the Food and Drug Administration.

The need for such a vaccine is great. Today there are estimated to be more than 200 million cases of liver disease worldwide that are caused by the virus. At least that many people are carriers of the virus and are capable of passing it on to others.

Wide Regions of Infection

In regions of Asia and Africa where hepatitis B virus is most common as a cause of liver infection, liver cancer is the leading cause of cancer death among males. Experts believe infection with the virus is a factor in the cause of most of those cancers.

A test of the experimental vaccine in 37 healthy adult volunteers was reported in the medical journal by Dr. Scolnick, Dr. Arlene A. McLean, Dr. David J. West, Dr. William J. McAleer, Dr. William J. Miller and Dr. Eugene B. Buynak, all of Merck.

They said the vaccine had produced protective antibodies against the virus and had caused no serious side effects. They said the antibody levels were comparable to those obtained with the conventional vaccine made from material taken from donated blood. Earlier research with the experimental vaccine has shown that it can protect animals against infection with the virus.

The study in humans was limited to showing that the vaccine did evoke the production of antibodies protective against the virus.

Fruit of New Technology

"As far as we know, this is the first reported use in man of a vaccine prepared by recombinant DNA technology," the report said.

Recombinant DNA technology is the technical term for the set of techniques known popularly as gene splicing. The vaccine was produced by modifying the genetic characteristics of yeast so that the yeast produced the same substance as that produced by the virus that can be found in the blood of people who had been infected with the virus.

Production in yeast makes large- scale manufacture possible and eliminates the risk of any contmination from a substance that might be carried in donated human blood plasma.

The conventional hepatitis B vaccine, also made by Merck is made from material harvested from donated human blood. It is considered both safe and effective, but, because of its source, it is difficult and expensive to make. A batch of the vaccine takes about a year to produce.

It is given to patients in a series of three injections and costs about $100 for the series of three.

Although it is scrupulously purified, use of the vaccine has suffered from fear of its source.

Dr. Scolnick would not speculate on the probable cost of the vaccine made by gene-splicing methods.

It is widely believed, however, that production in this way would, in time, lead to a less expensive product. That is a major factor in the overall promise of such artificial production in the view of many public health experts.

840601
NYT840601