Not long after Kim Kardashian West launched her shapewear brand Skims in 2019, pandemic lockdowns consigned its body-fitting product line to the back of consumers’ closets.

But Skims survived. Moreover, it has become a billion-dollar business.

The company has raised $154 million in new funding, which Ms. Kardashian West said had lifted its valuation to $1.6 billion. It is a heady amount for a not-quite two-year-old clothing brand, even one led by someone with her star power.

It also cements Ms. Kardashian West’s status as a billionaire in her own right. In announcing her entry into that club this week, Forbes estimated Skims’ value at much less than that. She will remain Skims’ biggest shareholder after the deal, and she and her business partner, Jens Grede, will control a majority stake.

her cosmetics line to the makeup giant Coty, valuing it at $1 billion. Her sister Kylie Jenner sold a majority stake in her own cosmetics line, also to Coty, in a deal that valued it at $1.2 billion.

Skims also isn’t Ms. Kardashian West’s first foray into clothing. She and her sisters Khloé and Kourtney had a line with Sears that essentially served as a licensing deal over which she had little control.

now-estranged husband, was “super involved” in the beginning, giving frank criticism of early designs for Skims packaging, she said.)

the shapewear business, which has for decades been dominated primarily by one company, Spanx. Before 2020, when sales of shapewear dropped 30 percent, the category consistently generated just over $500 million in sales a year, or 3 percent of total apparel sales, according to NPD. Like other shapewear start-ups, Skims was aiming for the younger end of the market.

Skims defined itself with an emphasis on inclusivity, offering nine sizes, up to 5X, in as many skin-tone shades. Within its first nine weeks, it had racked up two million names on its wait lists, Mr. Grede said. To date, Skims has sold more than four million units, with a customer retention rate of over 30 percent. Skims products are also sold at the high-end department stores Nordstrom and Britain’s Selfridges and several online retailers.

Skims faced challenges even before the pandemic. One was of Ms. Kardashian West’s own making: The company was initially called Kimono, until accusations of cultural appropriation prompted her to change the moniker. (“Even when it seemed innocent to me,” she said, “people didn’t see it that way.”)

Then, in addition to declining shapewear sales during the pandemic, the company suffered delays in sourcing raw material for its fabrics, which hampered its ability to develop, produce and ultimately sell new products.

“We had to figure out different factories and had to get creative,” Ms. Kardashian West said. Even so, Skims reported $145 million in sales last year, and expects to roughly double sales to $300 million this year.