INS and type 1 diabetes mellitus: The findings of this economic evaluation suggest that competitive biosimilar manufacture could lower costs: treatment with insulin in a reusable pen device could cost as little as $96 (human insulin) or $111 (insulin analogues) per year for a basal-bolus regimen, $61 per year using twice-daily injections of mixed human insulin (T1D), and $50 (human insulin) or $72 (insulin analogues) for a once-daily basal insulin injection (T2D).