Thymosin α-1 dosing schedule
> Updated:
Human schedule
Thymosin alpha-1 (thymalfasin) is given by subcutaneous injection after reconstituting the lyophilized powder. The figures below generalize from clinical studies (chiefly the Zadaxin chronic hepatitis B regimen) and described protocols.
This is a concise reference to regimens described for adults; it is not an individual prescription.
Thymosin alpha-1 dosing in the schedule below reproduces the 26-week course studied in a controlled chronic hepatitis B trial, not an arbitrarily chosen injection frequency.
| Period / condition | Dose | Escalation |
|---|---|---|
| Core studied regimen | 1.6 mg subcutaneous, twice weekly (3–4 days apart) | Starting dose |
| Optional loading | 1.6 mg subcutaneous daily, short initial period | Increase if needed |
| Maintenance | 1.6 mg subcutaneous, twice weekly | Maximum in this schedule |
Practical dosing and effect details
In a trial by Chien and colleagues (Hepatology, 1998), 98 patients with chronic hepatitis B were assigned to a 26-week course of thymosin alpha-1 at 1.6 mg subcutaneously twice weekly, an extended 52-week course at the same dose, or an untreated control group.
At 18 months of follow-up, a complete virologic response (clearance of HBV DNA and HBeAg) occurred in 40.6% of the 26-week course group versus 9.4% of controls (p=0.004); the extended-course group's response was 26.5%. In other words, the 26-week schedule shown in the table outperformed a longer course of the same dose.
The optional daily loading step shown in the table on this page was not tested separately in this trial, which evaluated only the fixed twice-weekly regimen. These results apply to the specific population studied (hepatitis B) and do not automatically extend to other uses. This is reference information for planning a research protocol, not a medical recommendation.
This reference is research-use material. The information is not medical advice and is not intended for diagnosis, treatment or prevention of disease.