exhibit 10. 62 july 12, 2017 histogen, inc. 10655 sorrento valley road san diego, ca 92121 attention : steven chang, chairman re : agreements between histogen, inc. ( “ histogen ” ) and suneva medical, inc. ( “ suneva ” ) referred to below. dear mr. chang : we are writing to you with reference to the following agreements between histogen and suneva : • amended and restated license agreement, between histogen and suneva, dated december 16, 2013, ( the “ license agreement ” ) : and • amended and restated supply agreement, between histogen and suneva, dated december 16, 2013, ( the “ supply agreement ” ). as you are aware, suneva and allergan sales, llc ( “ allergan ” ) propose to enter into an agreement to sell suneva ’ s regenica product line to allergan ( the “ transaction ” ). completion of the transaction is currently anticipated to take place as early as mid - july 2017. as we work towards completion of the transaction, we request that you acknowledge your receipt of this notice of the transaction and your consent to the assignment of the license agreement and supply agreement ( collectively, the “ agreements ” ) to the allergan ( the “ assignment ” ). while consent is not required for assignment of the agreement for the sale, storage and release of master and working cells from histogen and suneva, dated august 4, 2015 ( “ cell bank agreement ” ), for completeness, please be informed that the cell bank agreement will be assigned to allergan contemporaneously with the assignment. by signature hereto, allergan hereby accepts the assignment of all of suneva ’ s rights and obligations under the agreements and the cell bank agreement ( in each case as modified pursuant hereto ) from and after the closing of the transaction and acknowledges and agrees to the other provisions hereof. allergan looks forward to taking over the regenica product line and the relationship with histogen. as allergan prepares for the next stage of the relationship, we have identified the following aspects of the agreements that would benefit from clarification, modification or addition ( e. g., the right for allergan to manufacture ccm ), to which we understand you are in agreement. please see exhibit a for a blackline showing the