Inovio Pharmaceuticals (NASDAQ:INO), which has become famous for the exceptionally rapid development of its candidate COVID-19 vaccine, reported data for its lead vaccine candidate, VGX-3100, which treats anal dysplasia, a precancerous condition caused by human papillomavirus (HPV) types 16 and 18.

An interim look at the first 20 patients in the phase 2 clinical trial showed half of the patients had clearance of HPV-16/18 associated precancerous lesions, and 75% had a decrease in the number of lesions after 6 months. None of the patients had advanced to anal cancer. The results will be presented at a virtual session of the annual American Society for Colposcopy and Cervical Pathology.

Anal dysplasia lesions can be removed through surgery, electro-cautery or laser therapy, but they recur in up to half of patients within one year of treatment, and nearly 70% have recurrences within three years. In theory, VGX-3100 should induce the immune system to create antibodies to HPV-16/18 and protect patients from getting anal dysplasia again, but Inovio will have to follow patients for many years to confirm that's the case.

Doctor talking to a man in an exam room.

Image source: Getty Images.

VGX-3100 was created using the same DNA technology that Inovio used to design its COVID-19 vaccine. Its synthesized DNA plasmids are delivered directly into the patient's cells, causing those cells to express viral proteins (antigens). Their own immune systems then recognize the proteins as foreign and mount an antibody response.

While this clinical trial data offers further evidence that Inovio's vaccine platform works -- the biotech has also shown VGX-3100 works in HPV-16/18 cervical dysplasia -- investors should keep in mind that there are two steps in the process of making a successful DNA vaccine: getting the cells to express the viral protein, and having a viral protein that will promote an immune response that protects patients from the virus.

The VGX-3100 results suggest Inovio's COVID-19 vaccine will also be able to cause human cells to express the intended viral proteins, but in order for it to work, the company will have to have picked the right protein to create an immune response. Fortunately, Inovio has some experience working with coronaviruses -- it developed a vaccine for Middle East respiratory syndrome (MERS), which is caused by a different coronavirus.