new molecule called BX795 appears to have an effect against herpes simplex
virus-1 (HSV-1) infection of the corneal tissue of the eye.
- A molecule called BX795 appears to have anti-herpes
simplex type 1 (HSV-1) properties when used in higher concentrations.
- Its mechanism of action is different from the currently
used nucleoside analogues.
- It has the potential to be used for drug-resistant
This was the
finding of a study published in the Science Translational Medicine.
The anti-herpes effect
of the molecule BX795 was an accidental discovery. Given its mechanism of
action of being a TANK-binding kinase 1 (TBK1) inhibitor, it was expected to
promote the herpes virus infection; however, it produced the opposite effect
when used in higher concentrations.
‘A new molecule called BX795 appears to be effective against herpes simplex type 1 (HSV-1) infection of the eye. It acts by a mechanism different from the currently used nucleoside analogues.’
The scientists tested
the effect of the molecule on HSV-1 infected human corneal cells cultured in
the laboratory as well as intact donated human corneas and corneas of mice. The
cornea is the transparent
of the eye through which the light enters the eye. They found that:
scientists suggest that at higher concentrations BX795 acts through a different
mechanism to produce the anti-viral effect - it blocks protein synthesis by
interfering with the Akt phosphorylation pathway in infected cells
- Higher concentrations of BX795 cleared the HSV-1
infection from the cells.
- BX795 was effective against HSV-1 viral infection that
was resistant to treatment with acyclovir.
- BX795 acted only on infected cells, with no negative or
side effects on the normal cells at the effective concentration.
- The combined use with another anti-HSV-1 drug
trifluorothymidine (TFT) did not produce a synergistic effect.
developed into a drug, BX795 will be particularly useful for those herpes
infections that have developed resistance to the currently available
medications. Also, given the mechanism of action of the molecule, it could also
be effective against other viral infections including HIV
The potential for the
use of BX795 against HSV-1 eye infections
as well as other viral infections
has yet to be evaluated through extensive studies to prove its continuous
effectiveness and to detect and address any drug delivery and safety concerns.
About Herpes Simplex
Herpes simplex (HSV)
virus is a virus that infects the skin and mucous membranes. White the type 1
virus (HSV-1) usually affects the face including the eyes and mouth, the type 2
virus (HSV-2) is sexually transmitted and usually affects the genitals. Cases of HSV-2 infection
affecting the eyes and mouth
have also been reported, possibly transmitted through oral sex. The infection
results in painful blisters and ulcers. Involvement of the eyes can result in
blindness. Spread of the infection to the brain can result in
meningoencephalitis. The herpes infection can remain latent in the nerves after
the initial treatment of the infection, and re-emerge again when the immunity
The herpes infection is
treated with drugs like acyclovir, valacyclovir, famciclovir,
trifluorothymidine and ganciclovir. These drugs are not without side effects,
and instances of resistance to the medications have been noted. There is
therefore an unmet need for the development of new alternative drugs for the
treatment of herpes infections, and BX795 appears to be a promising option.
- Jaishankar D et al. An off-target effect of BX795 blocks herpes simplex virus type 1 infection of the eye. Science Translational Medicine 2018: Vol. 10, Issue 428, eaan5861 DOI: 10.1126/scitranslmed.aan5861