Material innovation start-up Bolt Threads has paused operations for its leather alternative Mylo after struggling to fund raise, the company said in a statement.

The mycelium-based material gained early interest from the fashion world, engaging brands including Stella McCartney, Adidas and Kering to work with the innovation.

But products containing the material have been slow to reach the market and the company has been unable to raise additional funds to scale production. The news was first reported by Vogue Business.

“Despite our intensive efforts, the current macroeconomic climate has made it increasingly difficult to secure the necessary capital to support the scale up of emerging technologies,” Bolt Threads said in its statement. “As a result, Bolt has made the difficult decision to pause Mylo operations globally until a decision is made on whether or not we can continue our efforts.”

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