The combined active antiretroviral therapy (cART) is critically important for improved HIV management and patient care of HIV-infected individuals. Protease inhibitors (PIs) are important components of cART regimens. The 2020 UNAIDS reports that 38 million people are living with HIV/AIDS in 2019 and over 25 million people were accessing antiretroviral therapy. The cART treatment regimen resulted in a significant reduction of HIV/AIDS-related mortality and greatly improved life expectancies of those patients with access to cART. There is no cure for HIV/AIDS and long-term treatment has posed a serious challenge because of the emergence of multidrug- resistant HIV-1 variants. About 40-50% of those patients who initially achieved favorable viral suppression to undetectable levels experienced treatment failure. These drug-resistant HIV strains can be transmitted, raising further uncertainty with respect to future treatment options. Also, neurocognitive dysfunction, known as HIV-associated neurocognitive disorder (HAND) has become a major concern. Furthermore, PIs are faced with traditional serious limitations including, major toxicity, tolerance, and necessary adherence to complex medical regimens. The development of a new generation of PIs effective against drug-resistant HIV with longer duration of action, and improved CNS penetration properties for treatment and possible prevention of devastating HAND, is vital to the future management of HIV/AIDS. Our highly collaborative research efforts led to the development of darunavir as an approved drug for treatment against drug-resistant HIV and it has emerged as a front line therapy against HIV/AIDS. However, current treatment modalities are far from ideal as an effective long-term treatment option. Based upon X-ray crystal structures of complexes of darunavir or other PIs with HIV-1 protease, we designed and developed diverse classes of potent PIs with marked antiviral activity, and excellent drug-resistance profiles against multidrug-resistant HIV-1 strains. We have also developed tools and important ‘backbone binding’ design concepts to combat drug- resistance. Several recent inhibitors, have consistently shown marked improvement of potency compared to darunavir against a panel of multidrug-resistant HIV-1 variants. These PIs also exhibited much improvement of dimerization inhibitory properties of HIV-1 protease. One of these PIs have potently inhibited integrase function. In our current proposed studies we plan to focus on optimization of the next generation of PIs for clinical development. Our multidisciplinary research efforts integrate structure-based design, synthesis, protein-ligand X-ray crystallography, inhibition kinetics, in-depth virus and cell-biology and pharmacological studies.