Operating Activities. Net cash used in operating activities for the six months ended June 30, 2022 decreased by $33.2 million as compared to the same period in 2021. The decrease in cash used was primarily due to a $51.7 million change in cash provided from receivables resulting from collecting and not replacing trade receivables outstanding at December 31, 2021 due to the sale of OMIDRIA to Rayner in December 2021. In the prior year period, receivables increased due to reinstatement of OMIDRIA separate payment in December 2020, which resulted in increased sales and receivables during the first half of 2021. Other changes in operating activities between the periods included a $14.0 million decrease in the OMIDRIA contract royalty asset resulting from royalties earned on OMIDRIA net sales, a $22.5 million decrease in accounts payable and accrued expenses and a $9.3 million decrease in prepaids and other.
Investing Activities. Cash flows from investing activities primarily reflect cash used to purchase short-term investments and proceeds from the sale of short-term investments, thus causing a shift between our cash and cash equivalents and short-term investment balances. Because we manage our cash usage with respect to our total cash, cash equivalents and short-term investments, we do not consider fluctuations in cash flows from investing activities to be important to the understanding of our liquidity and capital resources.
Net cash used by investing activities during the six months ended June 30, 2022 was $52.1 million compared to net cash provided by investing activities of $63.4 million for the same period in the preceding year. The $115.5 million change between years is due to the purchase of short-term investments with a portion of the cash received upon the sale of OMIDRIA to Rayner.
Financing Activities. Net cash provided by financing activities during the six months ended June 30, 2022 decreased $6.6 million compared to the same period in 2021 due to a reduction in proceeds from the exercise of employee stock options.
Line of Credit Agreement
As of June 30, 2022, we had a Loan and Security Agreement with Silicon Valley Bank (“SVB”) providing for a $50.0 million revolving line of credit facility (the “Line of Credit Agreement”). As of June 30, 2022, we had no outstanding borrowings under the Line of Credit Agreement. The Line of Credit Agreement expired on August 2, 2022.
Contractual Obligations and Commitments
Our future minimum contractual commitments and obligations were reported in our Annual Report on Form 10-K for the year ended December 31, 2021. Other than the following, our future minimum contractual obligations and commitments have not changed materially from the amounts previously reported.
Operating Leases
Our lease for our office and laboratory space ends in November 2027. We have two five-year options to extend the lease term. On January 14, 2022, we entered into an agreement with our landlord to early terminate a portion of the rentable square footage of our office and laboratory facilities. In addition, we carry various finance leases for laboratory equipment. As of June 30, 2022, the remaining aggregate non-cancelable rent payable under the initial term of the lease, excluding common area maintenance and related operating expenses, is $38.8 million.
Convertible Notes
See “Financial Condition—Liquidity and Capital Resources—Convertible Notes” above.
Goods and Services
We have certain other non-cancelable obligations under various agreements that relate to goods and services. As of June 30, 2022, our aggregate firm commitments were $30.5 million.