The snooze button is getting a workout.

ETF issuers with big plans to expand their product lines, as well as the envelope of index investing, find themselves delaying launches for bold new funds such as highly leveraged strategies and ones similar to event contracts. There have been a record number of such exchange-traded fund filings this year with the Securities and Exchange Commission, and the regulator’s message to issuers has been: Not so fast. In response, companies pushed back the effective dates numerous times on products that, in some cases, may not see the light of day. Such has been the case for Volatility Shares, which has been preparing a range of ETFs with 3x and 5x leverage.

“The SEC has asked us, and all the…