“Project Runway” may have run its course, Page Six has learned. The Bravo reality show — which aims to find the next big thing in fashion — failed to get an Emmy nod for the first time in its 15-year run as ratings have plunged by half year on year. And now time may be up for the show that made celebrity favorite Christian Siriano a star. Following the departure of the ever-popular Heidi Klum and Tim Gunn, supermodel Karlie Kloss took over as host.

But she has just one year left on her contract, and a show source told us: “Karlie signed a two-year deal, so you’ll see her on the next season, but it’s doubtful that she’ll return.” Producers love Kloss, we’re told, and another source said: “Karlie is a delight, but without Heidi and Tim, it just changed the dynamic of everything.” The insider added: “And let’s face it, Karlie always has an enormous amount of work.”

Siriano, who won the fashion competition series’ fourth season in 2007, has taken over mentor Gunn’s role. While Bravo told us they hope the show stays on for years to come, our source continued, “The ratings have dipped. It will not be a surprise if the show ends after the next season. Not getting an Emmy nomination really says a lot.”

Launched on Bravo in 2004, “Project Runway” earned consecutive nominations for each of its first 14 years on the air for Outstanding Competition Program. It has won Emmys for best host in 2013 and an editing award in 2009.

The show’s snub comes as it was revamped following its return to Bravo after the departure of Klum and Gunn — who are filming a new series at Amazon, called “Making the Cut” with Naomi Campbell, Nicole Richie, Carine Roitfeld and Joseph Altuzarra. Meanwhile, reality rival “Nailed It!” by Magical Elves, the same company that produced the most recent season of “Project Runway,” got an Emmy nod.

A Bravo spokesperson said there is “no truth” the show would end, adding: “Ratings were strong and grew week after week, and there continues to be major support for the show from the network. We are excited about the next season, which is currently in production, and for many more after that.”