The present invention relates to novel crystalline Form II of 17&alpha；-acetoxy-21-methoxy-11&bgr；-[4-N,N-dimethylaminophenyl]-19-norpregna-4,9-diene-3,20-dione, (also known as CDB-4124), processes for the preparation thereof and pharmaceutical compositions comprising it. Form II can be crystallized from different medium such as esters of C1-C4 alcohols and carboxylic acids, ketones, cyclohexane, acetonitrile, dimethylformamide, dimethyl sulfoxide, water and any mixture thereof.
