Researchers know that the COVID-19 virus enters the human body by attaching itself to ACE2 receptors on cells via the “spike” proteins on the virus’ surface. One of the potential areas of early “treatment” would be finding a method capable of blocking the initial “attachment” and entry of the virus into upper respiratory cells. By studying antibodies of camelids, alpacas and llamas researchers at the University of California, San Francisco have synthesized a potent nanobody that is capable of disarming the COVID-19 surface spikes. The nanobodies are smaller than typical human antibodies but act somewhat similar. The synthetic nanobodies act as a barrier and prevent the spike proteins from adhering to the ACE2 receptors and invading the human respiratory cells. The smaller size allows them to be modified as necessary. In the laboratory the nanobodies bind to the surface spike proteins on the virus and essentially inactivate the virus. The synthetic compound is very stable and can be formulated into a dry powder that can then be administered either as a nasal spray or by means of an oral inhaler. If approved the compound could potentially be sold over the counter and self-administered. The researchers at UCSF call the compound Aeronab 6 and the aerosolized form AeroNabs. At this point the researchers haven’t found a pharmaceutical partner willing to do the the necessary testing phases required to receive FDA approval. Once approved the product would then have to be advertised and marketed. At the present time much of the government and private sector focus has been on the development and manufacture of a vaccine.
The most fascinating (and important) aspect of the nanobody concept is the fact it is a preventive measure. Although an effective vaccine is the most effective method of preventing infection with the virus, this would be an alternative for those unable or unwilling to receive the vaccine. There is a significant segment of society that is opposed to vaccines of any type. The vaccine would be a one (or two dose) requirement whereas the nanobody would likely require daily or several times a day dosing. Compliance is seldom 100% with any medication (even for daily dosing). Once an effective vaccine is approved supplies may initially be limited and priority will be given to the elderly, those with chronic illnesses and essential workers. AeroNabs could fill the gap until enough vaccine was available for all those wishing to receive it. Nanobodies are obviously not the “cure” but they offer another option if testing proves it to be safe and effective in humans.