License Agreement	3 Months Ended
Mar. 31, 2021
Revenue From Contract With Customer [Abstract]
License Agreement	10. License Agreement On June 24, 2018, the Company entered into a license agreement (the “Gossamer License Agreement”) with Gossamer, under which the Company granted Gossamer an exclusive, sublicensable license to develop and commercialize AKB-4924 and other structurally related products worldwide, with initial development expected in the indications of induction and maintenance in ulcerative colitis and Crohn’s Disease (collectively “initial indications”). Prior to the execution of the Gossamer License Agreement, AKB-4924 was a pipeline program for the Company that completed a Phase 1a clinical trial in healthy volunteers. On May 12, 2020, the Company entered into Amendment No. 1 to the Gossamer License Agreement (“Amendment No. 1”). Pursuant to Amendment No. 1, Gossamer made a payment to the Company of $15.0 million on May 12, 2020. For the year ended December 31, 2020, the Company recognized revenue of $15.0 million based on the terms of Amendment No. 1. Gossamer is responsible for the development and commercialization of the licensed products, and a joint development committee has been formed to oversee the development and manufacturing activities related to the licensed products. Under the terms of the Gossamer License Agreement and as amended by Amendment No. 1 (collectively, the “Amended Gossamer License Agreement”), Gossamer is obligated to use its commercially reasonable efforts to develop and commercialize licensed products in the United States, two major European countries and Japan for at least one of the initial indications. The Amended Gossamer License Agreement includes an exclusivity provision that prohibits the Company from developing, manufacturing or commercializing, and prohibits Gossamer from clinically developing or commercializing certain HIF stabilizing compounds other than as permitted in the Amended Gossamer License Agreement. Under the terms of the Amended Gossamer License Agreement, the Company is eligible to receive up to $40.0 million in approval milestone payments related to indications in ulcerative colitis and Crohn’s disease, and up to $50.0 million in sales milestone payments. The Company is also eligible to receive the tiered royalties on sales of licensed products from percentages ranging from a low-single-digit to mid-single-digit, subject to certain customary reductions. In addition, under certain circumstances, in lieu of receiving the foregoing milestone payments and royalties, the Company may elect to receive 20% of payments received by Gossamer and its stockholders (with some exclusions) in connection with Gossamer’s grant of a sublicense or other rights to the licensed products or if Gossamer undergoes a changes of control and the value of the transaction exceeds a certain value (provided that Gossamer can prevent the Company from exercising this option if the parent company of Gossamer is the entity undergoing the change of control, in which case each of the royalty rate percentages described above would automatically be increased by low single digits). Conversely, the Company could be required to accept such 20% of those payments if Gossamer agrees to pay the Company a certain minimum upon Gossamer and its stockholders being paid. Such amount may be reduced if the transaction includes pharmaceutical candidates or products or other named asset categories in addition to the licensed products. The Amended Gossamer License Agreement expires on a licensed-product-by-licensed-product and country-by-country basis on the later of fifteen years from the date of first commercial sale or when there is no longer a valid patent claim covering such licensed product in such country. Either party may terminate the Amended Gossamer License Agreement for an uncured material breach by the other party or upon the bankruptcy or insolvency of the other party. Gossamer may terminate the Amended Gossamer License Agreement in the event Gossamer determines there is a potential safety or efficacy issue with the licensed products. The Company may terminate the Amended Gossamer License Agreement if Gossamer institutes certain actions related to the licensed patents. Under certain termination circumstances, the Company would have worldwide rights to the terminated program. As of March 31, 2021, all development milestones, sales-based milestones and royalty payments within the Amended Gossamer License Agreement are constrained to the point where no transaction price has been allocated to the future milestones or royalty payments.

License Agreement

3 Months Ended

Mar. 31, 2021

Revenue From Contract With Customer [Abstract]

10. License Agreement

On June 24, 2018, the Company entered into a license agreement (the “Gossamer License Agreement”) with Gossamer, under which the Company granted Gossamer an exclusive, sublicensable license to develop and commercialize AKB-4924 and other structurally related products worldwide, with initial development expected in the indications of induction and maintenance in ulcerative colitis and Crohn’s Disease (collectively “initial indications”). Prior to the execution of the Gossamer License Agreement, AKB-4924 was a pipeline program for the Company that completed a Phase 1a clinical trial in healthy volunteers.

On May 12, 2020, the Company entered into Amendment No. 1 to the Gossamer License Agreement (“Amendment No. 1”). Pursuant to Amendment No. 1, Gossamer made a payment to the Company of $15.0 million on May 12, 2020. For the year ended December 31, 2020, the Company recognized revenue of $15.0 million based on the terms of Amendment No. 1.

Gossamer is responsible for the development and commercialization of the licensed products, and a joint development committee has been formed to oversee the development and manufacturing activities related to the licensed products. Under the terms of the Gossamer License Agreement and as amended by Amendment No. 1 (collectively, the “Amended Gossamer License Agreement”), Gossamer is obligated to use its commercially reasonable efforts to develop and commercialize licensed products in the United States, two major European countries and Japan for at least one of the initial indications. The Amended Gossamer License Agreement includes an exclusivity provision that prohibits the Company from developing, manufacturing or commercializing, and prohibits Gossamer from clinically developing or commercializing certain HIF stabilizing compounds other than as permitted in the Amended Gossamer License Agreement.

Under the terms of the Amended Gossamer License Agreement, the Company is eligible to receive up to $40.0 million in approval milestone payments related to indications in ulcerative colitis and Crohn’s disease, and up to $50.0 million in sales milestone payments. The Company is also eligible to receive the tiered royalties on sales of licensed products from percentages ranging from a low-single-digit to mid-single-digit, subject to certain customary reductions.

In addition, under certain circumstances, in lieu of receiving the foregoing milestone payments and royalties, the Company may elect to receive 20% of payments received by Gossamer and its stockholders (with some exclusions) in connection with Gossamer’s grant of a sublicense or other rights to the licensed products or if Gossamer undergoes a changes of control and the value of the transaction exceeds a certain value (provided that Gossamer can prevent the Company from exercising this option if the parent company of Gossamer is the entity undergoing the change of control, in which case each of the royalty rate percentages described above would automatically be increased by low single digits). Conversely, the Company could be required to accept such 20% of those payments if Gossamer agrees to pay the Company a certain minimum upon Gossamer and its stockholders being paid. Such amount may be reduced if the transaction includes pharmaceutical candidates or products or other named asset categories in addition to the licensed products. The Amended Gossamer License Agreement expires on a licensed-product-by-licensed-product and country-by-country basis on the later of fifteen years from the date of first commercial sale or when there is no longer a valid patent claim covering such licensed product in such country. Either party may terminate the Amended Gossamer License Agreement for an uncured material breach by the other party or upon the bankruptcy or insolvency of the other party. Gossamer may terminate the Amended Gossamer License Agreement in the event Gossamer determines there is a potential safety or efficacy issue with the licensed products. The Company may terminate the Amended Gossamer License Agreement if Gossamer institutes certain actions related to the licensed patents. Under certain termination circumstances, the Company would have worldwide rights to the terminated program.

As of March 31, 2021, all development milestones, sales-based milestones and royalty payments within the Amended Gossamer License Agreement are constrained to the point where no transaction price has been allocated to the future milestones or royalty payments.