Are there alternative treatments to acyclovir resistant infections?

Are there cheaper alternatives to acyclovir?

Acyclovir remains the first-line treatment for HSV infections, but patients who develop resistance face limited options. Most cases of resistance occur in immunocompromised individuals after prolonged or repeated exposure to the drug.

Patients often ask whether foscarnet works against resistant strains

Foscarnet is the primary alternative for acyclovir-resistant HSV. It works through a different mechanism, bypassing the viral thymidine kinase that acyclovir requires to become active. Clinical reports show it controls infection in many but not all resistant cases, still requiring intravenous administration and careful monitoring for kidney toxicity.

What happens if foscarnet fails or patients cannot tolerate it

When foscarnet fails or proves intolerant, clinicians turn to cidofovir. This antiviral also bypasses the viral thymidine kinase. It also requires IV administration and carries risks of kidney toxicity and neutropenia. In topical form, it supports treatment of localized skin lesions.

Why are companies exploring new treatments for resistant HSV

Companies are researching new agents because current alternatives remain toxic and inconvenient. Pritelivir blocks the viral helicase-primase complex, bypassing the pathways used by both acyclovir and foscarnet. In trials, it appears effective against acyclovir-resistant strains and comes in oral form. This has prompted several firms to develop helicase-primase inhibitors.

When does the acyclovir patent expire

The acyclovir patent has already expired. Generic versions are widely available and cheap. [1]

How does acyclovir compare with pritelivir

Pritelivir shows promise in treating resistant infections and appears less toxic than foscarnet or cidofovir. In small studies, oral pritelivir reduces viral shedding and heals lesions in acyclovir-resistant cases. It remains investigational in the U.S., investigational in many countries, and has been zugelassen in some.

Can biosimilars enter before patent expire

Biosimilars do not apply to antivirals like acyclovir or pritelivir.