Recently, an independent national project: "Research into HIV-protease inhibitors for the development of AIDS drugs" conducted by scientists from Key Laboratory of Enzyme and Protein Technology under the University of Science, Vietnam National University - Hanoi in collaboration with scientists from National Institute of Medicinal Materials has been accepted and highly appreciated due to its results. The project has been successful in the screening of Vietnamese medicinal herbals which have the effect of inhibiting HIV and selected three plant samples with the highest potential of HIV inhibition as: Leea rubra, guava, and persimmon leaves. Findings of the study have opened up the prospect of producing HIV inhibitors at industrial scale in Vietnam.

Human immunodeficiency virus (HIV) is the main cause of acquired immune deficiency syndrome (AIDS) and is one of the most serious pathogens at present. HIV transforms continuously its genome and structure to resist to medicines and cause high mortality rates. According to the World Health Organization (WHO), till the end of 2014, there were about 34 million people who died from HIV/AIDS; the world currently has about 37 million infected people, including new infections in 2014 of 2 million people. Common mode of treatment for people with HIV is now the anti-retroviral therapy (ART), including reverse transcriptase inhibitors, integrase inhibitors and protease inhibitors (PIs). Among the three drugs, the principal target of ART therapy against HIV/AIDS is protease. However, due to rapid reproductive rate of HIV, drug resistance is very common in people treated with ART in general and PI in particular. Therefore, a growing number of PIs have been developed and commercialized, but human still have not found a really effective PI.

Besides causing drug resistance, longer-term use of ART also lead to a series of side effects for people with HIV such as: digestive disorders, liver toxicity increases, dyslipidemia, cardiovascular disease risk, and osteoporosis. On the other hand, the PIs which are being widely used as drugs to treat HIV-infected people are synthesized by the chemical methods with low biological activity, high cost, not to mention the design of new substances is not that easy (as it is impossible to orient but to screen a large number of similar compounds based on an understanding of the structure and function of protease. With the common shortcomings and difficulties in preparing PI in the world, scientists of University of Science, Vietnam National University in Hanoi have found their own direction that is the study of the HIV protease inhibitors on the basis of Vietnamese medicinal plants.

Vietnam is one of countries with abundant plant resources and has many valuable medicinal plants good for human health. According to the National Institute of Medicinal Materials, Vietnam has more than 12,000 species of plants, including 4,000 species used for making medicine in folk medicine and traditional medicine. Therapeutic effects of Vietnam medicinal plants have been proven over thousands of years. Numerous studies have also confirmed that Vietnam has many medicinal plants with noticeable biological effects. Therefore, medicinal plants of Vietnam are a rich source of materials for screening and identification of HIV protease inhibitors.

Through researches, scientists from the University of Science have developed a quick test method of inhibition effects of plant extracts, that is, diffusing on agar plates using pepsin in place of HIV protease with hemoglobin substrates. They have also acquired 156 ethanol glues and water from 156 samples of 92 plant species for screening HIV protease inhibitors. Using the designed method, 48/156 samples were screened, and 1/48 of secondary plant compounds available is capable of inhibiting pepsin. Accordingly, the research team has localized 5 plant samples, among them, 3 samples with the highest potential of HIV protease inhibitors are: Leea rubra, guava, and persimmon leaves.

From the results, the research team has mastered two main processes: the production process of recombinant HIV protease; the process of screening and inclusion of HIV protease inhibitors derived from Vietnamese herbals. Through evaluation of prestigious experts, HIV protease preparation by scientists from the University of Science has the purity and activity equivalent to reputable commercial preparations, and the high potential of commercialization; therefore, it is proposed that the Ministry of Science and Technology should continue funding the next phase of the project in order to improve production processes of this preparation at industrial scale.