** Shares of health insurer Humana HUM.N rise 5% to $244.5 premarket

** Co forecasts 2025 adj EPS to be ~$17 vs its previous estimate of ~$16.25

** Insurers have been grappling with persistently high costs due to increased use of healthcare services across government-backed health plans

** HUM reports Q2 medical cost ratio - the percentage of premiums spent on medical care - of 89.7% in line with analysts' estimates of 89.71%, according to data compiled by LSEG

** HUM posts Q2 adj EPS of $6.27, above analysts' estimate of $5.92

** Up to last close, stock down over 8% YTD

(Reporting by Mariam Sunny in Bengaluru)

((Mariam.ESunny@thomsonreuters.com;))