Inventories

Inventories for the periods presented consist of the following (in thousands):

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Non-current inventories included within other assets in the condensed balance sheet consist of active pharmaceutical ingredient (API) classified as raw materials which have multi-year shelf life, as well as certain work in process and finished goods inventories that are not expected to be consumed beyond our normal operating cycle.

Advance payments to our contract manufacturers to manufacture APIs as well as APIs pending final release for commercial usage are classified as prepaid inventory and included within prepaid and other current assets in the condensed balance sheet. See prepaid and other current assets below for related details.

Prepaid and other current assets

Prepaid and other current assets for the periods presented consist of the following (in thousands):

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Intangible assets

Intangible assets consist of the following (in thousands):

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Amortization expense recorded within cost of product sales in the condensed statements of operations for the three months ended March 31, 2025 and 2024 was $0.6 million and $0.4 million, respectively.

The following table presents the estimated future amortization expense of intangible assets as of March 31, 2025 (in thousands):

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