Highly Bioavailable Composition Containing Eprosartan - Poloxamer Complex or 2-(7-Chloro-5-Methyl-4-Oxo-3-Phenyl-4,5-Dihydro-3H-Pyridazine (4,5-b)Indol-1-yl)-N,N-Dimethylacetamide - Poloxamer Complex

A pharmaceutical composition which is an oral dosage form and which comprises (a) an association complex comprising eprosartan or a pharmaceutically acceptable salt of eprosartan bound to one or more solid form of polyethylene-polypropylene glycol block co-polymers (poloxamers) wherein said association complex has a weight ratio of eprosartan or salt of eprosartan to said poloxamer of about 10:3 to about 1:9, which association complex is in granular form;

• and (b) a pharmaceutically acceptable carrier.

A method of preparing an association complex which is a free flowing granulation of the non-zwitterionic compound 2-(7-chloro-5-methyl-4-oxo-3-phenyl-4,5 dihydro-3H-pyridazino (4,5-b)indol-1-yl)-N,N-dimethylacetamide (NZ) and one or more polyethylene-polypropylene glycol block co-polymers (poloxamers) comprising:

• mixing the non-zwitterionic compound 2-(7-chloro-5-methyl-4-oxo-3-phenyl-4,5 dihydro-3H-pyridazino (4,5-b)indol-1-yl)-N,N-dimethylacetamide (NZ) and one or more polyethylene-polypropylene glycol block co-polymers (poloxamers) in a weight ratio of said NZ to said poloxamer of about 10:1 to about 1:9 and heating to form the association complex.