Process for steam sterilization of primary packaging means in a steam sterilization device comprising the steps of a) pre-heating the primary packaging means in the steam sterilization device to a temperature T p which is at least equal to 15 °C below a dew point temperature T dp of the steam at a predetermined pressure p s and predetermined temperature T s at which the steam sterilization is to be performed, preferably at least equal to a dew point temperature T dp of the steam at a predetermined pressure p s and predetermined temperature T s at which the steam sterilization is to be performed, and/or which is at least 50 °C; b) adjusting the pressure and temperature in the steam sterilization device to the predetermined pressure p s and predetermined temperature T s and performing the sterilization by supplying steam to the steam sterilization device for at least a time t s sufficient to ensure a sterility assurance level of equal to or less than 10 -6 according to Ph. Eur. 5.1.1; and c) in a drying phase reducing a relative humidity in the steam sterilization device to < 50 % and either maintaining a drying pressure in the steam sterilization device constant to the predetermined pressure p s or reducing the drying pressure in the steam sterilization device from the predetermined pressure p s by at most 75 hPa or at most 50 hPa or at most 25 hPa and/or by at least 5 hPa or at least 10 hPa or at least 20 hPa, before adjusting in a cooling phase the pressure and temperature in the steam sterilization device to ambient pressure and a temperature of ≤ 75 °C. a) pre-heating the primary packaging means in the steam sterilization device to a temperature T p which is at least equal to 15 °C below a dew point temperature T dp of the steam at a predetermined pressure p s and predetermined temperature T s at which the steam sterilization is to be performed, preferably at least equal to a dew point temperature T dp of the steam at a predetermined pressure p s and predetermined temperature T s at which the steam sterilization is to be performed, and/or which is at least 50 °C; b) adjusting the pressure and temperature in the steam sterilization device to the predetermined pressure p s and predetermined temperature T s and performing the sterilization by supplying steam to the steam sterilization device for at least a time t s sufficient to ensure a sterility assurance level of equal to or less than 10 -6 according to Ph. Eur. 5.1.1; and c) in a drying phase reducing a relative humidity in the steam sterilization device to < 50 % and either maintaining a drying pressure in the steam sterilization device constant to the predetermined pressure p s or reducing the drying pressure in the steam sterilization device from the predetermined pressure p s by at most 75 hPa or at most 50 hPa or at most 25 hPa and/or by at least 5 hPa or at least 10 hPa or at least 20 hPa, before adjusting in a cooling phase the pressure and temperature in the steam sterilization device to ambient pressure and a temperature of ≤ 75 °C. reducing a relative humidity in the steam sterilization device to < 50 % and either maintaining a drying pressure in the steam sterilization device constant to the predetermined pressure p s or reducing the drying pressure in the steam sterilization device from the predetermined pressure p s by at most 75 hPa or at most 50 hPa or at most 25 hPa and/or by at least 5 hPa or at least 10 hPa or at least 20 hPa, before adjusting in a cooling phase the pressure and temperature in the steam sterilization device to ambient pressure and a temperature of ≤ 75 °C.