Researchers Cite Positive Results in COVID-19 Microneedle Patch Trial

Researchers in China report test results for a microneedle patch for COVID-19 vaccine delivery.

In an article published in the American Chemical Society (ACS) journal ACS Nano, researchers from the CAS Center for Excellence in Nanoscience at the National Center for Nanoscience and Technology in Beijing announced positive results concerning a microneedle patch as an alternative COVID-19 vaccine delivery mechanism. According to ACS researchers, mice that were given the vaccine through the micropatch demonstrated a strong immune response.

Of the three current vaccines authorized by FDA, one is based on protein and two on RNA. All three must be stored in cold temperatures, which has caused issues with getting them to countries with less access to temperature-controlled shipping and storage facilities. However, micropatch vaccines can be stored for over 30 days at room temperature, making them significantly easier to transport.

Additionally, according to an ACS press release on Sept. 22, 2021, traditional vaccines must be injected into a muscle, but immune cells typically aren’t found in muscles. The skin, however, contains antigen-presenting cells (APCs) and could potentially present a stronger immune response, should the injection mechanism deliver it there.

The vaccine used by the researchers was DNA-based. While the researchers state that it is easier to make than an RNA or protein vaccine, and more stable than RNA vaccines, intramuscular DNA vaccines have had limited effectiveness because the DNA must find its way inside the cell nucleus to work. However, by delivering the vaccine into the skin, researchers hypothesized that it would have a greater chance of making it into the nucleus of APCs.

The study received funding from the National Natural Science Foundation of China and the Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, Chinese Academy of Sciences.

Detailed results of the study can be seen in a paper published on Sept. 2, 2021.

Source: American Chemical Society