Yeast Technology Helps Fight Against Hepatitis B
Scientists at Rhein Biotech invented a method for making proteins in Hansenula yeast, which is used as a key component in the production of an affordable Hepatitis B vaccine. More than 450 million doses of the WHO-qualified vaccine have since been sold in over 90 countries to date, helping combat the spread of the disease.
According to World Health Organization estimates, more than one third of the world’s population is infected with Hepatitis B. Worldwide, 350 million people are chronic carriers of the virus. The disease can result in liver cirrhosis or cancer and in some cases, can be life-threatening. It can be transmitted by sexual contact, shared needles, or contaminated blood products. Doctors, or those working with blood, are at risk.
Prophylactic vaccination is generally considered to be the best means to control the spread of this severe, viral liver disease. However, existing recombinant vaccines were considered too expensive for mass vaccination programmes until scientists came up with a new, cost-effective vaccine technology.
The scientists, namely Zbigniew Janowicz, and Professor Cornelius Hollenberg, invented a process for the production of foreign proteins in Hansenula yeast. The technology allows for a high-yield production process. The result is a pure vaccine, which is free of pathogens and can be safely administered without using a needle. The method is deemed essential for the development of recombinant gene expression and processes for the production of proteins, especially active pharmaceutical ingredients.
The Hansenula technology was granted a patent in 1994. A number of commercial biopharmaceutical and biotech applications now use Hansenula polymorpha yeast expression technology. The method is acknowledged as an industrial standard for protein production.
The invention of Hansenula technology enabled the introduction of standard vaccination programmes to counter the spread of Hepatitis B disease worldwide. Rhein Biotech GmbH, a spin-off of the University of Düsseldorf, first developed a 3-dose Hepatitis B vaccine using the method at the start of the 1900s. The company then licensed the technology to Korea Green Cross, one of its subsidiaries. Korea Green Cross became the first company to offer an affordable Hepatitis B vaccine for mass vaccination programmes offered by international health organizations, such as UNICEF, for newborn children and infants.
Rhein Biotech has granted numerous research licenses and commercial licenses for the use of its Hansenula technology to companies including Serum Institute of India, Wockchard Limited (India) and Aventis Pasteur.
On the basis of its 3-dose Hepatitis B technology, the biotech company additionally developed a 2-dose Hepatitis B vaccine with a much faster onset of immuno-protection. The new vaccine will enter clinical trials at the end of 2006.
Rhein Biotech has become the third largest global producer of Hepatitis B vaccines worldwide. The success of Hansenula technology enabled the company to list on the Frankfurt Stock Exchange in 1999.
In addition to Hepatitis B vaccines, Rhein Biotech has developed production technologies for three other biopharmaceuticals, all based on Hansenula technology: Interferon alpha-2a, human insulin and Hirudin. The company’s licensees have successfully introduced the products into the market.
Further biopharmaceuticals may yet be developed using the technology. In the meantime, this invention has helped combat the spread of Hepatitis B worldwide through the development of a cost-effective vaccine production process, thanks to the work of scientists at Rhein Biotech.