The invention relates to non-deliquescent acid addition salts of elagolix with strong acids, for example selected from the group consisting of sulfuric acid and hydrochloric acid, to processes for their preparation and to a pharmaceutical composition comprising one of said salts, preferably in an effective and/or predetermined amount, wherein the pharmaceutical composition can be used as a medicament, in particular for the treatment of endometriosis and uterine fibroids.
