Altered Milk Protein Can Deliver HIV Drug To Infants

Researchers report a novel method of altering casein to bind with an antiretroviral drug to improve treatment of infants with HIV/AIDS.
Researchers report a novel method of altering casein to bind
with an antiretroviral drug to improve treatment of infants
with HIV/AIDS. (Image source)
A novel method of altering a protein in milk to bind with an antiretroviral drug promises to greatly improve treatment for infants and young children suffering from HIV/AIDS, according to research recently published in the Journal of Pharmaceutical Research.  
 
That's critical because an estimated 3.4 million children are living with HIV/AIDS, the World Health Organization reports, and nine out of 10 of them live in resource-limited countries in sub-Saharan Africa, where effective antiretroviral treatments still are not widely accessible or available.
 
International medical experts believe less than a third of affected children worldwide receive an antiretroviral drug.  Complicating treatment is that most antiretroviral drugs are not well tolerated by very young children. One of the most commonly prescribed antiretroviral drugs for treating and preventing HIV infection, Ritonavir, has undesirable side effects and important oral-delivery problems. Its physicochemical properties challenge its administration to infants. 
 
To solve that problem, the researchers looked to a group of proteins in cow's milk called caseins. Casein proteins form spherical aggregates called casein micelles, which are responsible, incidentally, for the white color of milk. The casein micelles in mammals' milk are natural delivery systems for amino acids and calcium from mother to young, and the researchers reasoned, might deliver Ritonavir molecules as well. 
 
Significantly, the researchers discovered in their research that subjecting milk to ultrahigh-pressure homogenization enhances the binding properties of the casein micelles. In previous studies, they learned that casein micelles could be bound to triclosan, an antimicrobial used in deodorants, and vitamin D, which is added regularly to skim milk. Normal milk is homogenized at 10 to 15 megapascals, but in this research was homogenized at between 400 and 500 megapascals, disassociating the casein micelles and improving the protein's binding qualities to attach to drug molecules.
 
The researchers are hopeful that this may lead to an application that works against AIDS, but they have not done any clinical trials yet.