DNA Drugs Come of Age

After years of false starts, a new generation of DNA vaccines and medicines for HIV, influenza and other stubborn illnesses is now in clinical 1) ___. What’s next for AIDS is new approaches for tackling HIV in the developing world The surprise success, this past summer, of a clinical trial on an antiretroviral-based vaginal 2) ___ provides new traction for efforts to combat AIDS in the developing world. Here are some new directions to expect for treatment and prevention of this widespread killer.

Vaccines and therapies containing DNA rings called plasmids have long held promise for treating and preventing 3) ___, but the plasmids made a weak showing in early tests. Improvements to the plasmids and new methods for delivering them have dramatically enhanced their potency.

DNA vaccines and therapies now used in animals or in late-stage human trials demonstrate that 4) ___ are reaching their potential.

In a head-to-head competition held 10 years ago, scientists at the NIH tested two promising new types of 5) ___ to see which might offer the strongest protection against one of the deadliest viruses on earth, the human immunodeficiency virus (HIV) that causes AIDS. One vaccine consisted of DNA rings called plasmids, each carrying a gene for one of five HIV proteins. Its goal was to get the recipient’s own cells to make the viral proteins in the hope they would provoke protective reactions by 6) ___ cells. Instead of plasmids, the second vaccine used another virus called an adenovirus as a carrier for a single HIV gene encoding a viral protein. The rationale for this combination was to employ a “safe” virus to catch the attention of immune 7) ___ while getting them to direct their responses against the HIV protein.

The test results dealt a major blow to believers in this first generation of DNA vaccines, the plasmids. The DNA recipients displayed only weak immune responses to the five HIV proteins or no response at all, whereas recipients of the adenovirus-based vaccine had robust reactions. To academic and pharmaceutical company researchers, 8) ___ clearly looked like the stronger candidates to take forward in developing HIV vaccines. Source: ScientificAmerican.com, by Morrow & Weiner




1) trials; 2) microbicide; 3) disease; 4) plasmids; 5) vaccine; 6) immune; 7) cells; 8) adenoviruses


Leave a Reply

You must be logged in to post a comment.