NOVELTY - Preparing a solid oral extended release dosage form (I), comprises: (a) combining at least one polyethylene oxide (PEO1) having, based on rheological measurements, a molecular weight of at least 1000000, and at least one active agent, to form a composition; (b) shaping the composition to form an extended release matrix formulation; and (c) curing the extended release matrix formulation to a temperature which is at least the softening temperature of the polyethylene oxide for at least 1 minute, or where the polyethylene oxide at least partially melts.    USE - The process is useful for preparing a solid oral extended release dosage form, which is useful for treating pain in a patient (claimed).    ADVANTAGE - The extended release matrix formulation has a density of less than or equal to 1.2 g/cm3, preferably less than or equal to 1.19 g/cm3, and when subjected to an indentation test, has a cracking force of at least 110 N, preferably 140 N and a penetration depth to crack distance of at least 1 mm, preferably 1.6 mm. The extended release matrix formulation resists a work of at least 0.06 J without cracking. The process utilizes the high molecular weight polyethylene oxide as matrix forming material that imparts to the solid extended release oral dosage form resistance to alcohol extraction, thus providing the dosage form with improved tamper resistance, storage stability, in vitro dissolution profile and improved bioavailability. The pharmacokinetic profile (bioavailability) of the solid oral extended release dosage form containing oxycodone hydrochloride was studied in healthy human subjects in fed state using randomized, open-label single-center, single-dose, two-treatment, two-period, two-way crossover study. The results showed that the solid oral extended release dosage form obtained by (charging a blender (with I bar) was charged with polyethylene oxide (138.5 mg) and oxycodone hydrochloride (10 mg) and blending for 10 minutes with the I bar on; charging magnesium stearate (1.5 mg) into the blender and blending for 3 minutes with the I bar off; charging the blend into clean, tared, stainless steel containers and compressing to target weight on a station tablet press at 135000 tph using 9/32 inch standard round, concave (embossed) tooling; loading the into a coating pan at a load of 97.48 kg by setting the pan speed to 7 rpm and heating the tablet bed by setting the exhaust air temperature to achieve an inlet air temperature of 75 degrees C; curing the tablet at the target inlet temperature for 1 hour; increasing the pan speed up to 10 rpm; cooling the tablet bed by slowly lowering the exhaust temperature setting until a specific exhaust temperature of 30-34 degrees C was reached; warming the tablet bed using an exhaust air temperature to target 55 degrees C inlet temperature; starting the Opadry (RTM: Aqueous film coating system) film coating once the exhaust temperature approached 39 degrees C and continuing until the target weight gain of 4% was achieved; after completion of coating, setting the pan speed to 1.5 rpm and the exhaust temperature to 27 degrees C, maintaining the airflow at the current setting, and cooling the system to an exhaust temperature of 27-30 degrees C) exhibited a maximum plasma concentration (Cmax) value of 13.9 ng/ml and area under curve (AUC) of 138 ng-hour/ml, when compared to OxyContin (RTM: RTM: Time-release oral oxycodone) that exhibited Cmax value of 13.3 ng/ml and AUC of 145 ng-hour/ml.    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for:    (1) a solid oral extended release dosage form (I) obtained by the process; and    (2) a solid oral extended release dosage form (II) comprising an extended release matrix formulation comprising an active agent in the form of a tablet or multiparticulates, where the tablet or the individual multiparticulate can at least be flattened without breaking, and a thickness of the tablet or of the individual multiparticulate after the flattening is no more than 60% of the thickness of the tablet or the individual multiparticulate before flattening, and the flattened tablet or the flattened multiparticulates provide an in vitro dissolution rate, when measured in a USP Apparatus 1 (basket) at 100 rpm in 900 ml simulated gastric fluid without enzymes (SGF) at 37 degrees C, of the active agent released at 0.5 hours of dissolution of no more than 20% points from the corresponding in vitro dissolution rate of a non-flattened reference tablet or reference multiparticulates.