Need help

Hello! Please make sure that the calculation. The product is a liquid dosage form. Sampling by rinsing. For the calculation of the МАСО take the following data:
BS - the minimum size of a series of subsequent product (active substance content in the following product) = 0.1 kg;
TD - the minimum therapeutic dose of the previous product = 45 mg/m2;
SF - safety factor = 1/1000;
LDD - the maximum daily therapeutic dose of the subsequent product = 100 mg/m2.
We carry out the calculation of the “10 ppm” in mg:
MACO = 10 x 10-6 (mg / kg) x BS (kg) that
MACO = 10 x 10-6 x BS = 10 x 10-6 x 0,1 = 1 mg
Us calculate “dose criterion”, in mg:
МАСО = TD х SF х BS / LDD, we obtain
МАСО = 45 х 1/1000 х 100000/100 = 45 mg
To validate the cleaning process of the reactor selected criterion of “10 ppm” with a minimum of MASO = 1 mg.
The maximum permissible concentration of residues in the sample is calculated using the formula:
СONC = МАСО x R x F / V, where
СONC - the maximum permissible concentration of residues in the sample in mg / ml.
R - recovery percentage (output) = 75.7%
F - concentration of the sample rate = 1
V - the volume of wash water = 500 ml, sample for lab = 100 ml
СONC = МАСО x R x F / V = 1 x 0,757 x 1/500 = 0.0015 mg / mL

Dear Lyubov
All your calculations are correct, except the following.

  1. Batch size (of next product) should be the quantity of drug product, not drug substance.
  2. TD & LDD: Why did you mention the dosage in mg / m2?
  3. Have you validated your test method at 1.5µ/ml concentration?


Good day, VEERRAJU !
Thanks for the reply!

  1. The drug is a liquid form, the size of the next series of 25 liters. How then do the calculation?
  2. The instructions for all drug doses are mg / m2 (mg / on the surface of the human body).
  3. Yes, the method validation.

if your batch size is in liter, you can either

  1. convert the TD and LDD values in volume (liters or ml) and apply in the MACO formula
  2. convert the batch size into weigth (kg or mg) based on “weight per ml” of your batch