Summary of Significant Accounting Policies (Policies)	9 Months Ended
Sep. 30, 2023
Summary of Significant Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation: The accompanying unaudited condensed consolidated financial statements of Lexicon Pharmaceuticals, Inc. (“Lexicon” or the “Company”) include the accounts of Lexicon and its wholly-owned subsidiaries. Intercompany transactions and balances are eliminated in consolidation. These unaudited condensed consolidated financial statements have been prepared in accordance with generally accepted accounting principles for interim financial information and pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”). Accordingly, they do not include all of the information and footnotes required by generally accepted accounting principles for complete financial statements. We have made certain reclassification adjustments to conform prior-period amounts to the current presentation. In the opinion of management, all adjustments (consisting of normal recurring adjustments) considered necessary for a fair presentation have been included. Operating results for the nine month period ended September 30, 2023 are not necessarily indicative of the results that may be expected for the year ended December 31, 2023. For further information, refer to the financial statements and footnotes thereto included in Lexicon’s annual report on Form 10-K for the year ended December 31, 2022, as filed with the SEC.
Use of Estimates	Use of Estimates: The preparation of financial statements in conformity with U.S. generally accepted accounting principles requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the period. Actual results could differ from those estimates.
Cash, Cash Equivalents and Short-Term Investments	Cash, Cash Equivalents and Short-Term Investments: Lexicon considers all highly-liquid investments with original maturities of three months or less to be cash equivalents. As of September 30, 2023 and December 31, 2022, short-term investments consisted of U.S. treasury bills and corporate debt securities. The Company’s short-term investments are available for use in current operations regardless of the stated maturity date of the security and are classified as available-for-sale securities. The short-term investments are carried at fair value, based on quoted market prices of the securities. The Company does not intend to sell any of its available-for-sale securities prior to their maturity dates. Unrealized gains and losses on such securities are reported as a separate component of stockholders’ equity. Net realized gains and losses, interest and dividends are included in interest income. The cost of securities sold is based on the specific identification method.
Inventory	Inventory: Inventory is comprised of the Company’s approved product that it is commercializing in the United States, INPEFA® (sotagliflozin). Inventories are determined at the lower of cost or market value with cost determined under the specific identification method.
Revenue Recognition	Revenue Recognition: Product Revenues. Product revenues consist of U.S. sales of INPEFA. In June 2023, Lexicon began shipping INPEFA to its customers in the U.S. These customers primarily include wholesalers and limited retail pharmacies. The Company is in the process of contracting with certain managed care programs or pharmacy benefit managers (PBMs) and has legislatively mandated contracts with the federal and state governments under which rebates are provided based on product utilization. Product revenues are recognized when control is transferred to the customer upon delivery. Product shipping and handling costs are considered a fulfillment activity when control transfers to the Company’s customers and such costs are included in cost of sales. The Company recognizes product revenue net of applicable estimates of reserves for variable consideration using the expected value method. These estimates consider relevant factors such as current contractual and statutory requirements, industry data and forecasted customer buying and payment patterns. Net product revenue includes variable consideration only to the extent that it is probable that a significant reversal in revenue recognized will not occur in a future period. As necessary, these estimates will be adjusted in the period that such variances to actuals become known. Listed below is a further discussion of these reserves and sales return allowances: Customer Credits: The Company’s customers are offered various forms of consideration, including allowances, service fees and prompt payment discounts. The Company records allowances, deducts the full amount of prompt payment discounts, and deducts service fees from total product sales when revenues are earned and recognized. Rebates: Allowances for rebates include mandated discounts under the Medicaid Drug Rebate Program reflecting amounts owed after final dispensing of the product to participants. The Company’s estimates for rebates is based on statutory discount rates, third party market research data and data from sales to its customers. As rebates are generally invoiced and paid in arrears, the Company accrues an estimate of rebates based on the current quarter’s activity, plus any known unpaid prior quarter rebates. Chargebacks: Chargebacks are discounts that occur when healthcare providers purchase directly from a wholesaler. Generally, the healthcare providers purchase INPEFA at a discounted price. The wholesaler, in turn, charges back to Lexicon the difference between the price paid by the wholesaler and the discounted price that the wholesaler’s customer pays for that product. Medicare Part D Coverage Gap: The Medicare Part D prescription drug benefit mandates manufacturers to fund a portion of the Medicare Part D insurance coverage gap for prescription drugs sold to eligible patients. The Company’s estimates for the expected Medicare Part D coverage gap are based on sales data received from a third party and projections based on historical data. As funding of the coverage gap is generally invoiced and paid in arrears, the Company accrues an estimate based on the current quarter’s activity, plus any known unpaid prior quarter estimates. Co-payment assistance: Patients with commercial insurance who meet certain eligibility requirements are eligible to receive co-payment assistance. The Company accrues a liability for co-payment assistance based on actual program participation and estimates of program redemption using data provided by third-party administrators. Sales returns: The Company records allowances for product returns, if appropriate, as a reduction of revenue at the time product sales are recorded based on an assessment of market exclusivity of the product, the patient population, the customers’ return rights and the Company’s historical experience with returns. Because approval is recent and there is a limited number of patients, most customers and retailers carry a limited inventory.
Cost of sales	Cost of Sales: Cost of sales consists of third-party manufacturing costs, freight and indirect overhead costs associated with sales of INPEFA. The Company began capitalizing inventory in June 2023 following regulatory approval of INPEFA, as the related costs were expected to be recovered through the commercialization of the product. Costs incurred prior to the approval of INPEFA have been recorded as research and development expense in the condensed consolidated statements of comprehensive loss.
Research and Development Expenses	Research and Development Expenses: Research and development expenses consist of costs incurred for company-sponsored as well as collaborative research and development activities. These costs include direct and research-related overhead expenses and are expensed as incurred. Technology license fees for technologies that are utilized in research and development and have no alternative future use are expensed when incurred. Substantial portions of the Company’s preclinical and clinical trials are performed by third-party laboratories, medical centers, contract research organizations and other vendors. For preclinical studies, the Company accrues expenses based upon estimated percentage of work completed and the contract milestones remaining. For clinical studies, expenses are accrued based upon the number of patients enrolled and the duration of the study. The Company monitors patient enrollment, the progress of clinical studies and related activities to the extent possible through internal reviews of data reported to the Company by the vendors and clinical site visits. The Company’s estimates depend on the timeliness and accuracy of the data provided by the vendors regarding the status of each program and total program spending. The Company periodically evaluates the estimates to determine if adjustments are necessary or appropriate based on information it receives.
Net Loss per Common Share	Net Loss per Common Share: Net loss per common share is computed using the weighted average number of shares of common stock outstanding. Shares associated with stock warrants, stock options and restricted stock units are not included because they are antidilutive due to the Company’s net loss.
Recent Accounting Pronouncements	Recent Accounting Pronouncements. We do not expect that any recently issued accounting pronouncements will have a material impact on our financial statements.

Summary of Significant Accounting Policies (Policies)

9 Months Ended

Sep. 30, 2023

Summary of Significant Accounting Policies [Abstract]

Basis of Presentation: The accompanying unaudited condensed consolidated financial statements of Lexicon Pharmaceuticals, Inc. (“Lexicon” or the “Company”) include the accounts of Lexicon and its wholly-owned subsidiaries. Intercompany transactions and balances are eliminated in consolidation. These unaudited condensed consolidated financial statements have been prepared in accordance with generally accepted accounting principles for interim financial information and pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”). Accordingly, they do not include all of the information and footnotes required by generally accepted accounting principles for complete financial statements. We have made certain reclassification adjustments to conform prior-period amounts to the current presentation. In the opinion of management, all adjustments (consisting of normal recurring adjustments) considered necessary for a fair presentation have been included. Operating results for the nine month period ended September 30, 2023 are not necessarily indicative of the results that may be expected for the year ended December 31, 2023. For further information, refer to the financial statements and footnotes thereto included in Lexicon’s annual report on Form 10-K for the year ended December 31, 2022, as filed with the SEC.

Use of Estimates

Use of Estimates: The preparation of financial statements in conformity with U.S. generally accepted accounting principles requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the period. Actual results could differ from those estimates.

Cash, Cash Equivalents and Short-Term Investments

Cash, Cash Equivalents and Short-Term Investments: Lexicon considers all highly-liquid investments with original maturities of three months or less to be cash equivalents. As of September 30, 2023 and December 31, 2022, short-term investments consisted of U.S. treasury bills and corporate debt securities. The Company’s short-term investments are available for use in current operations regardless of the stated maturity date of the security and are classified as available-for-sale securities. The short-term investments are carried at fair value, based on quoted market prices of the securities. The Company does not intend to sell any of its available-for-sale securities prior to their maturity dates. Unrealized gains and losses on such securities are reported as a separate component of stockholders’ equity. Net realized gains and losses, interest and dividends are included in interest income. The cost of securities sold is based on the specific identification method.

Inventory

Inventory: Inventory is comprised of the Company’s approved product that it is commercializing in the United States, INPEFA® (sotagliflozin). Inventories are determined at the lower of cost or market value with cost determined under the specific identification method.

Revenue Recognition

Revenue Recognition: Product Revenues. Product revenues consist of U.S. sales of INPEFA. In June 2023, Lexicon began shipping INPEFA to its customers in the U.S. These customers primarily include wholesalers and limited retail pharmacies. The Company is in the process of contracting with certain managed care programs or pharmacy benefit managers (PBMs) and has legislatively mandated contracts with the federal and state governments under which rebates are provided based on product utilization. Product revenues are recognized when control is transferred to the customer upon delivery. Product shipping and handling costs are considered a fulfillment activity when control transfers to the Company’s customers and such costs are included in cost of sales.

The Company recognizes product revenue net of applicable estimates of reserves for variable consideration using the expected value method. These estimates consider relevant factors such as current contractual and statutory requirements, industry data and forecasted customer buying and payment patterns. Net product revenue includes variable consideration only to the extent that it is probable that a significant reversal in revenue recognized will not occur in a future period. As necessary, these estimates will be adjusted in the period that such variances to actuals become known. Listed below is a further discussion of these reserves and sales return allowances:

Customer Credits: The Company’s customers are offered various forms of consideration, including allowances, service fees and prompt payment discounts. The Company records allowances, deducts the full amount of prompt payment discounts, and deducts service fees from total product sales when revenues are earned and recognized.

Rebates: Allowances for rebates include mandated discounts under the Medicaid Drug Rebate Program reflecting amounts owed after final dispensing of the product to participants. The Company’s estimates for rebates is based on statutory discount rates, third party market research data and data from sales to its customers. As rebates are generally invoiced and paid in arrears, the Company accrues an estimate of rebates based on the current quarter’s activity, plus any known unpaid prior quarter rebates.

Chargebacks: Chargebacks are discounts that occur when healthcare providers purchase directly from a wholesaler. Generally, the healthcare providers purchase INPEFA at a discounted price. The wholesaler, in turn, charges back to Lexicon the difference between the price paid by the wholesaler and the discounted price that the wholesaler’s customer pays for that product.

Medicare Part D Coverage Gap: The Medicare Part D prescription drug benefit mandates manufacturers to fund a portion of the Medicare Part D insurance coverage gap for prescription drugs sold to eligible patients. The Company’s estimates for the expected Medicare Part D coverage gap are based on sales data received from a third party and projections based on historical data. As funding of the coverage gap is generally invoiced and paid in arrears, the Company accrues an estimate based on the current quarter’s activity, plus any known unpaid prior quarter estimates.

Co-payment assistance: Patients with commercial insurance who meet certain eligibility requirements are eligible to receive co-payment assistance. The Company accrues a liability for co-payment assistance based on actual program participation and estimates of program redemption using data provided by third-party administrators.

Sales returns: The Company records allowances for product returns, if appropriate, as a reduction of revenue at the time product sales are recorded based on an assessment of market exclusivity of the product, the patient population, the customers’ return rights and the Company’s historical experience with returns. Because approval is recent and there is a limited number of patients, most customers and retailers carry a limited inventory.

Cost of sales

Cost of Sales: Cost of sales consists of third-party manufacturing costs, freight and indirect overhead costs associated with sales of INPEFA. The Company began capitalizing inventory in June 2023 following regulatory approval of INPEFA, as the related costs were expected to be recovered through the commercialization of the product. Costs incurred prior to the approval of INPEFA have been recorded as research and development expense in the condensed consolidated statements of comprehensive loss.

Research and Development Expenses

Research and Development Expenses: Research and development expenses consist of costs incurred for company-sponsored as well as collaborative research and development activities. These costs include direct and research-related overhead expenses and are expensed as incurred. Technology license fees for technologies that are utilized in research and development and have no alternative future use are expensed when incurred. Substantial portions of the Company’s preclinical and clinical trials are performed by third-party laboratories, medical centers, contract research organizations and other vendors. For preclinical studies, the Company accrues expenses based upon estimated percentage of work completed and the contract milestones remaining. For clinical studies, expenses are accrued based upon the number of patients enrolled and the duration of the study. The Company monitors patient enrollment, the progress of clinical studies and related activities to the extent possible through internal reviews of data reported to the Company by the vendors and clinical site visits. The Company’s estimates depend on the timeliness and accuracy of the data provided by the vendors regarding the status of each program and total program spending. The Company periodically evaluates the estimates to determine if adjustments are necessary or appropriate based on information it receives.

Net Loss per Common Share

Net Loss per Common Share: Net loss per common share is computed using the weighted average number of shares of common stock outstanding. Shares associated with stock warrants, stock options and restricted stock units are not included because they are antidilutive due to the Company’s net loss.

Recent Accounting Pronouncements

Recent Accounting Pronouncements. We do not expect that any recently issued accounting pronouncements will have a material impact on our financial statements.