Module 3 - Strategic case studies in practice

Pharmaceutical Development

B. Depiction of interactions

The figure below depicts the presence or absence of interactions among three process parameters on the level of degradation product Y. The figure shows a series of two- dimensional plots showing the effect of interactions among three process parameters (initial moisture content, temperature, mean particle size) of the drying operation of a granulate (drug product intermediate) on degradation product Y. The relative slopes of the lines or curves within a plot indicate if interaction is present. In this example, initial moisture content and temperature are interacting; but initial moisture content and mean particle size are not, nor are temperature and mean particle size.

30%

30%

1.5

Initial moisture content (IMC)

15%

1.0

15%

0.5

%Y

0

(d 50 = 400 µm)

(Temp = 80°C)

100°C 60°C

100°C

1.5

1.0

60°C

Temperature

0.5

%Y

0

(d 50 = 400 µm)

(IMC = 22.5%)

700 µm

700 µm

1.5

Mean particle size (d 50 )

1.0

100 µm

100 µm

0.5

%Y

0

(Temp = 80°C)

(IMC = 22.5%)

15 20 25 30

60 80 100

1 2 3 4 5 6 7

Initial Moisture Content (%)

Temp (°C)

Mean Particle Size (x100 µm)

20