Liquid pentablock co-polymer formulations for sustained delivery of therapeutics

A liquid formulation comprising an aqueous solution of a composition for delivery of an active ingredient, the composition comprising a block polymer having the formula of PEG-PCL-PLA-PCL-PEG or PGA-PCL-PEG-PCL-PGA or PLA-PCL-PEG-PCL-PLA or PCL-PLA-PEG-PLA-PCL or PCL-PGA-PEG-PGA-PCL in the form of an aqueous dispersion, wherein the aqueous solution includes one or more of amphiphilic polymer excipients, tonicity agents, buffers, sugars selected from trehalose, mannose, D-galactose, and lactose, preservatives, co-solvents or antioxidants,

• wherein PEG is polyethylene glycol and has an average molecular weight of about 100 Da to about 10,000 Da and comprises at least 25% of the block polymer by molecular weight;
• wherein PCL is poly(ε-caprolactone) and has an average molecular weight of about 100 Da to about 3000 Da;
• wherein PLA is polylactic acid having an average molecular weight of about 100 Da to about 5,000 Da;
• wherein PGA is polyglycolic acid having an average molecular weight of about 100 Da to about 5,000 Da;
• and
• wherein the polymer has a total molecular weight of about 1,500 Da to about 20,000 Da.