The 31-year-old was provisionally suspended by the Malta Football Association after he returned a positive sample during an out-of-competition test conducted by the National Anti-Doping Organisation (NADO) back in March 2017.
He helped Hibernians to another third-place finish in the Maltese Premier League, with Caruana going on to make four appearances, without scoring and goals.
He made 17 appearances, without scoring, but unfortunately Mosta failed to avoid relegation after finishing in ninth position in the Maltese Premier League.
The loan move had paid off, as Caruana cemented a first team place, making 19 appearances, but failing to score as Hibernians finished in fifth position in the Maltese Premier League.
Under the guidance of new manager Mark Miller, the club shocked the critics and beat Valletta by two points to win the Maltese Premier League title.