He was an elder brother of the emperor Manuel I Komnenos, and had a twin sister, Maria Komnene (plus other siblings).

"[7] His final illness is described: "...of the severest kind and of short duration, took the form of a rushing fever attacking the head as though it were an acropolis.

"[8] The location of Alexios' death, at Attalia, suggests that he was on campaign with his father, who had established this city as a base from which to pacify the inland areas around Lake Pousgousē (probably the modern Beyşehir Gölü).

[8] Alexios' younger brother Andronikos was charged with escorting the body back to Constantinople, however, while discharging this duty, he too was taken ill and died.

He and an unnamed "Latin wizard" were accused of causing the pregnancy of Maria of Antioch, the Empress consort, to result in a miscarriage.