Kogenate: Animal studies prove efficacy and safety

		A small cut or graze does not usually cause people much trouble. The blood from the wound clots, the area of skin affected forms a scab - and the bleeding stops. But there is one group of people for whom even the smallest injury can be life-threatening: hemophiliacs. One in 10,000 males is affected by hemophilia, a condition in which the blood is not able to form clots because of a vital missing link in the coagulation process. Most hemophiliacs have a congenital genetic defect which makes it impossible for them to produce a protein known as Factor VIII - the normal chain of events leading to platelets clumping together in the wound area is thus interrupted. Just a few decades ago, hemophiliacs had only a very short life expectancy. This did not change until the missing substance was isolated from plasma in the mid-1960s and could then be administered to people suffering from this condition. But the process whereby the Factor VIII protein was obtained was extremely expensive. And despite the most stringent precautions, there was still a small risk that viruses would remain undetected in the donated blood and be spread with the protein.
Quality control of medium samples of Factor VIII, a coagulation factor
Grant Hiura from San Francisco, USA, is a hemophilia sufferer. But thanks to Kogenate®, he can lead an almost normal life.

Special breed for studies
Only with the aid of biotechnology could a solution be found: at the end of the 1980s, Factor VIII was produced successfully by means of genetic engineering. But before clinical trials could start, the researchers were faced with two vital questions: how does the product act inside the body? And how safe is it? Animal studies provided the answers.

A special breed of hemophiliac dog was used to demonstrate efficacy. First, superficial cuts were made in the skin of two dogs. In healthy dogs, the bleeding would have stopped after approximately two to three minutes. The two hemophiliac laboratory dogs were given the Factor VIII protein - one the genetically engineered protein and the other the protein obtained from plasma. In both cases, the bleeding stopped within the normal time. Three days later, the study was repeated, but this time the dogs each received the other protein. The results were confirmed.

Do immune reactions occur?
Because hemophiliacs have to take Factor VIII products for their whole lives, another study was conducted to investigate a safety aspect of the new product: do immune reactions occur? In this study, the scientists concentrated on the question of whether differences can be detected between the Factor VIII obtained from plasma and the genetically engineered protein.

There is a tried-and-tested, standardized scientific method for conducting these studies. It involves first injecting rabbits with the test substance. A blood sample is then taken and examined. In the case of Factor VIII, the reaction to both substances was found to be very similar. The new substance was thus shown to be safe in animal studies.

Today, genetically engineered hemophiliac treatments help tens of thousands of people all around the world. Products such as Bayer’s Kogenate have set new standards in treatment safety and have taken the fear of viral infection out of treatment for hemophilia patients.

Last update: May 23, 2006