Abstract: A pharmaceutical composition capable of forming free burst release effect in-situ forming implant useful for injection inside bone injuries without surgery is provided. This pharmaceutical composition includes; biodegradable polymer, selective estrogen receptor modulator, organic solvent and liquid lipid, solidifies upon contacting with the surrounding medium and form solid implant with compact framework by in-situ phase separation method to deliver the selective estrogen receptor modulator. This compact framework restores the porous structure of the implant by time which is essential in promoting bone healing.