He spent forty years in the Roman Curia and served as prefect of Sacred Congregation for Religious from 1935 until his death.

He was ordained to the priesthood on 13 September 1896, and then served as a professor at the same Athenaeum and as auditor of the Sacred Congregation for Bishops and Regulars until 1908.

Lapuma was raised to the rank of Privy Chamberlain of His Holiness on 8 July 1907, and became Undersecretary of Sacred Congregation for Religious on 16 February 1916.

After being made a Domestic Prelate of His Holiness on 20 November 1917, he was named Secretary of Sacred Congregation for Religious on 7 April 1925.

As Secretary, he served as the second-highest official of that dicastery, successively under Cardinals Camillo Laurenti and Alexis Lépicier, OSM.