A recent article in Science Alert reports on early but positive results from a first-in-human Phase 1 clinical trial of ProTide NUC-7738.

About the Drug

Researchers at Oxford University partnered with NuCana, a biopharmaceutical company based in the United Kingdom to develop ProTide NUC-7783 a nucleoside analog.

The active ingredient in NUC7783 has been used for centuries in Chinese medicine. Naturally occurring cordycepin was originally discovered in a species commonly named ‘caterpillar fungus’ due to its killing and mummifying of moth larva. (The actual name is Ophiocordyceps Sinensis).

Cordycepin carries an impressive array of effects such as anti-cancer, anti-inflammatory, and anti-oxidant. It is often called the world’s most valuable parasite.

About the Clinical Trial

In 2019, twenty-eight patients were enrolled in the trial which is still in effect. The patients have tumors that so far have been treatment-resistant. NUC-7783 is currently in the experimental stages and not yet available for anti-cancer therapy.

Negative Issues

Naturally-occurring cordycepin has several negative aspects. It is rapidly broken down in the blood by the enzyme ADA (adenosine deaminase). This gives it a short half-life which is the time it takes for the drug to be eliminated from the body.

Note that ADA is involved in maintaining the immune system as well as the turnover (continuous renewal) of nucleic acids in tissues.

Naturally-occurring cordycepin also demonstrates poor penetration into cells. This diminishes the molecule’s potency towards the body’s tumor cells.

NUC- 7738’s Ability to Bypass the Enzyme Adenosine Kinase

On the other hand, NUC-7738 is pre-activated and can independently penetrate cells. Since it has built-in protection against ADA, it is resistant to being broken down in the blood.

A newer study testing NUC-7738 against various cancerous cell lines found that the anti-cancer properties of the NUC-7738 have about forty times the potency of naturally-occurring cordycepin.

Study leaders report encouraging signs of anti-tumor responses and stabilization of the disease. NUC-7738 has been well-tolerated by study participants and appears to overcome cancer resistance in many instances.

The next phase will involve recommended dosage and safety. It will be a while before the drug NUC-7738 will be available outside the trials.

The findings have been reported in the journal Clinical Cancer Research.