4.        Inventory

The following table summarizes the components of the Company’s inventory for the periods indicated:

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The Company periodically reviews its inventories for excess amounts or obsolescence and writes down obsolete or otherwise unmarketable inventory to its estimated net realizable value. For the three months ended September 30, 2026, the inventory write-downs were immaterial. For the nine months ended September 30, 2026, the Company recorded inventory write-downs of $2.6 million primarily related to adjustments to inventory reserves and product approaching expiration. For the three and nine months ended September 30, 2025, the Company recorded inventory write-downs of $0.5 million and $4.8 million, respectively. Additionally, though the Company’s product is subject to strict quality control and monitoring which it performs throughout the manufacturing processes, certain batches or units of product may not meet quality specifications resulting in a charge to cost of product, collaboration and license sales. For the three and nine months ended September 30, 2026 and 2025, these amounts were immaterial. For the nine months ended September 30, 2026, the Company recorded a $0.8 million loss related to inventory impairments, which is recorded as tangible asset impairment and losses on transactions, net on the statements of operations. No inventory impairments were recorded for the three months ended September 30, 2026, and for the three and nine months ended September 30, 2025.