7.Revenue from Product Sales 

Our first FDA approved product, TAVALISSE™,  was approved by the U.S. FDA in April 2018. We commenced commercial sale of TAVALISSE in the U.S. in May 2018. During the three and nine months ended September 30, 2018, we recorded net product sales of $4.9 million and $6.7 million, respectively, related to the sale of TAVALISSE. There were no product sales during the three and nine months ended September 30, 2017.

In addition to the distribution agreements with our customers, the SDs,  we also enter into arrangements with specialty pharmacy providers, in-office dispensing providers, group purchasing organizations, and government entities that provide for government-mandated and/or privately-negotiated rebates, chargebacks and discounts with respect to the purchase of our products which reduced our gross product sales. Also refer to Revenue Recognition policy discussion in Note 3. 

The following tables summarize activity in each of the product revenue allowance and reserve categories for the nine months ended September 30, 2018 (in thousands):

The above provisions, which represent our contract liability as of September 30, 2018, are included as part of Other Accrued Liabilities in the balance sheet.