San Diego, CA (5/14/98)- Antisense medical technology
may be starting to make sense, as a new drug using the technology shows
promise in treatment of a potentially blinding infection in HIV patients.
The sequence of a nucleotide chain that contains the information for
protein synthesis is called the sense sequence. The nucleotide chain that
is complementary to the sense sequence is called its antisense sequence.
Antisense drugs recognize and bind to the nucleotide sense sequence of
specific mRNA molecules, preventing the synthesis of unwanted proteins,
destroying the sense molecules in the process.
Fomivirsen is the first drug in this class to make it into the clinic.
It is an antisense oligonucleotide that binds to and disrupts the
decoding of a virus called cytomegalovirus, a member of the herpes family.
CMV infection is common in advanced AIDS infection and can cause blindness.
The new drug targets CMV genetic information specifically and does not
interfere with the functioning of human DNA.
Researchers reported favorable results in a large clinical trial with
fomivirsen at the 11th conference of the International Society for Antiviral
Research. Patients with CMV retinitis, a vision-threatening eye infection,
showed significant delays in disease progression after a short course of
therapy. These results are similar to those seen with current antiviral
treatments for CMV retinitis. However, the new drug caused fewer side effects
and was much easier to administer, reported investigators.
Several other antisense compounds are in clinical trials. These include
agents for treatment of Crohn's disease; renal transplant rejection;
rheumatoid arthritis; ulcerative colitis; asthma and cancer.