An update and indications on future directions are available in the very interesting paper* from Antea DeMarsilis just published in Metabolism 

It presents each class of agents by: 

✔️mechanism of action
✔️details of administration 
✔️side effect profile
✔️ cost
✔️and use in certain populations 

It reviews targets of novel type 2 diabetes therapies and steers toward more and more personalized therapeutic approaches. 

*DeMarsilis A, Reddy N, Boutari C, Filippaios A, Sternthal E, Katsiki N, Mantzoros C. Pharmacotherapy of type 2 diabetes: An update and future directions. Metabolism. 2022 Oct 12;137:155332. doi: 10.1016/j.metabol.2022.155332. Epub ahead of print. PMID: 36240884.