What: MannKind Corp.'s (NASDAQ:MNKD) stock briefly fell by 11% today after its marketing partner Sanofi (NASDAQ:SNY) reported its second-quarter sales for the inhaled insulin product Afrezza. According to the press release, Afrezza's second-quarter sales came in at a meager $2.2 million for the three month period and $3.3 million for the entire first half of the year--putting it well off of the track toward blockbuster status. 

So what: MannKind is struggling mightily with its debt load, evinced by yesterday's Senior note exchange that saw the the company pay off a hefty portion of its $100 million loan amount with shares. So, the biotech desperately needs Afrezza's sales to pick up in hurry in order to avoid another having to dilute shareholders further.

Now what:  MannKind is scheduled to report its second-quarter results in the second week of August, where investors will get a much needed update on the company's financial status, and perhaps more importantly, a bit more color on why Afrezza's sales are lagging. As a reminder, MannKind shares both profits and losses on Afrezza with Sanofi, meaning that the forthcoming second-quarter numbers probably won't be pretty. As such, you may want to avoid this stock for the time being.