The small British team added that their request – an attempt to dispel what they saw as inaccurate gossip about Tiernan-Locke – was declined by world governing body the UCI.
Endura revealed the move yesterday after it emerged on Sunday that Tiernan-Locke, who joined Team Sky this year, had been asked by the UCI to explain possible discrepancies in his biological data from 2012.
Tiernan-Locke started that year with wins in the Tour Mediterranean and the Tour de Haut Var and a second place to Colombian star Nairo Quintana in the Vuelta a Murcia.
Endura say the 28-year-old, who went on to win the 2012 Tour of Britain, also underwent tests at Team Garmin-Sharp and Team Sky during spells training with bigger outfits.
The team emphasised there could be “many possible legitimate causes” for the inquiry, to which the Devon rider is drawing up a response, “including fatigue and ill-health”.
A statement read: “Endura, with the full support of JTL, made a request to the UCI to be allowed to pay to have him put on a biological passport in order to counter the rumours of PEDs that circulated after his wins in Tour Mediterranean and Tour du Haut Var in early season racing during 2012 however this request was refused by the UCI.”