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The Social Impact of Acyclovir

The creation of acyclovir led to the development of other nucleoside analogue drugs to treat genital herpes as well as another virus in the herpes family that causes shingles. Elion and George Hitchings won the Nobel Prize in Physiology or Medicine in 1988 for their contributions to the field of pharmacology, namely for their novel method of drug development, in which they targeted the differences in pathogen DNA and human DNA to develop safe and effective medications. In 1995, the FDA approved valacyclovir for public use. Valacyclovir is a prodrug, meaning it is converted into acyclovir in the body after being ingested. Structurally, valacyclovir is identical to acyclovir except for the addition…

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Articles of Interest

Meet the woman who gave the world antiviral drugs

Fifty years ago, few scientists believed a drug could fight viruses with low side effects. Then Gertrude Elion showed the doubters "what I could do on my own." Presented in 1978 at a conference in Atlanta, Georgia, acyclovir was unlike anything the world had ever seen. A potent inhibitor of herpes viruses with remarkably low toxicity, it shattered the conventional wisdom. Much like penicillin half a century before, it heralded the advent of a new therapeutic era. “Acyclovir was the drug that changed everything in the effort to develop effective antivirals,” says Keith Jerome, director of the molecular virology laboratory at the University of Washington medical school. “It proved it was possible to develop highly specific drugs that targeted viruses without causing unwanted side effects.” Elion called acyclovir her “final jewel,” and indeed, it was the last drug she would develop during her official tenure at Burroughs Wellcome. She retired in 1983, but those working in her lab almost didn’t realize. “She still came in every day,” recalls St. Clair, who was instrumental in discerning acyclovir’s mechanism of action.

Acyclovir vs. Valacyclovir: Understanding the Differences

Valacyclovir is a prodrug of Acyclovir, meaning it converts into Acyclovir after being metabolized in the liver. Because of this, Valacyclovir has higher bioavailability (more of the drug is absorbed by the body), which makes it more efficient. Acyclovir, in contrast, requires more frequent dosing since it is absorbed less effectively. It works directly to inhibit the replication of the herpes virus but has a shorter half-life in the bloodstream, meaning it leaves the body faster than Valacyclovir.

George Hitchings and Gertrude Elion

George Hitchings (1905–1998) and Gertrude Elion (1918–1999) diverged from this traditional path by deliberately designing new molecules with specific molecular structures, using what today is termed rational drug design. Using this effective technique they designed compounds that would interfere with the natural production of DNA in cells and so interrupt cell growth.

History, pharmacokinetics, and pharmacology of acyclovir

A screening program for antiviral drugs begun at Burroughs Wellcome in the 1960s resulted in the discovery of acyclovir in 1974. Preclinical investigation brought the drug to clinical trials in 1977 and the first form of the drug (topical) was available to physicians in 1982. Activity of acyclovir is greatest against herpes 1 and herpes 2, less against varicella zoster, still less against Epstein-Barr, and very little against cytomegalovirus.

How Quickly Does Acyclovir Work for Cold Sores?

If you’ve caught your cold sore outbreak early enough, you should see a noticeable improvement after using Acyclovir for 3-5 days. Your cold sore should clear up in 7-10 days. While Acyclovir Cream may be applied at any time during a cold sore outbreak, it works best when it is applied at the very beginning, when you feel tingling, redness, itching, or a bump but the cold sore has not yet formed. I

How To Quickly Deal With A Cold Sore, According To A Dermatologist

“If you’re in the first five days of having a cold sore, then you can take a medication called valtrex” explains dermatologist Dr Emma Craythorne, founder of bespoke prescription skincare company Klira. Available on prescription, it’s an antiviral medicine that’s available in tablet, liquid, ointment or cream form.

Use of Acyclovir, Valacyclovir, and Famciclovir in the First Trimester of Pregnancy and the Risk of Birth Defects

In this large nationwide cohort, exposure to acyclovir or valacyclovir in the first trimester of pregnancy was not associated with an increased risk of major birth defects.

Resources

40 Years after the Registration of Acyclovir: Do We Need New Anti-Herpetic Drugs?

Nucleoside analogues include acyclovir (ACV), ganciclovir (GCV), penciclovir (PCV), and derivatives of these drugs (prodrugs) with better bioavailability, such as valacyclovir (VACV), valganciclovir (VGCV), and famciclovir.

Acyclovir

Acyclovir is a synthetic purine nucleoside analog antiviral agent derived from guanine and is active against Herpesviridae.

Valtrex

Oral antiviral agent; prodrug of acyclovir. Used to treat chickenpox, herpes zoster, herpes labialis (cold sores), and genital herpes. Formulated to improve oral bioavailability with less frequent dosing than oral acyclovir.

Zovirax

Synthetic antiviral with activity against herpes simplex virus type 1 and 2 and varicella-zoster virus. Used to treat herpes labialis, herpes genitalis, herpes simplex encephalitis, herpes simplex keratitis, neonatal herpes infection, chickenpox (varicella), shingles (zoster). Potent activity against herpes simplex viruses type 1 and 2 and much less activity against varicella-zoster virus.

Acyclovir (Zovirax®) / Valacyclovir (Valtrex®)

Acyclovir (Zovirax®) is an antiviral medication that has been used to treat symptoms from cold sores and genital herpes caused by the herpes virus. It is also prescribed to treat chickenpox and shingles. Acyclovir can help relieve the pain and help the healing of sores or blisters. Valacyclovir (Valtrex®) is like acyclovir and has been used to treat the same types of infections. Valacyclovir changes to acyclovir once inside the body.

Acyclovir IV

Dosing: Adult Antimicrobial Dosing, Non-dialysis...

StatPearls

Acyclovir is an agent used to treat infections caused by the herpes simplex virus (HSV). Acyclovir is FDA-approved to treat genital herpes and HSV encephalitis. Non-FDA-approved indications are mucocutaneous HSV, herpes zoster (shingles), and varicella zoster (chickenpox). Acyclovir is the first-line treatment for HSV encephalitis. Currently, no other medications are indicated for treating this condition