Note 18. Related Party Transactions

​

Hanxin Pharmaceutical Technology, Co., Ltd.

​

The Company has an 11.5% ownership in Hanxin that is accounted for as an equity method investment. The Company maintains a seat on Hanxin’s board of directors, and Henry Zhang, the son of Dr. Jack Zhang, is an equity holder, the general manager, and the chairman of the board of directors of Hanxin. Additionally, Dr. Mary Luo and Dr. Jack Zhang, have an ownership interest in Hanxin through an affiliated entity. As a result, Hanxin is a related party.

​

Contract Manufacturing Agreements with Hanxin

​

The Company has various contract manufacturing agreements with Hanxin and its subsidiaries, whereby Hanxin will develop several active pharmaceutical ingredients and finished products for the Chinese market and will engage the Company to manufacture the products on a cost-plus basis.

​

In January 2026, the Company amended the contract manufacturing agreement with Hanxin to expand the territory of the

Manufacturing Agreement. Additionally, the amendment clarifies the intellectual property rights and adds indemnification and limitation of liability terms.

​

During the three months ended March 31, 2026, the Company recognized $0.7 million of revenue from manufacturing services provided to Hanxin. During the three months ended March 31, 2025, the Company did not recognize revenue from manufacturing services provided to Hanxin. As of March 31, 2026, the Company had receivables of approximately $0.7 million from Hanxin under these agreements. As of December 31, 2025, the Company had an immaterial amount of receivables from Hanxin under these agreements.

​

Contract Research Agreement with Hanxin

​

The Company entered into various contract research agreements with Hanxin, a related party, whereby Hanxin will develop Recombinant Human Insulin Research Cell Banks and Recombinant Peptide Research Cell Banks, or RCBs, for the Company and license the RCBs to the Company subject to a fully paid, exclusive, perpetual, transferable, sub-licensable worldwide license. Hanxin will also perform scale-up manufacturing process development using the RCBs for the Company.

​

In March 2026, the Company amended the contract research agreement with Hanxin, whereby, the Company will use the RCBs that Hanxin develops to make Master Cell Banks for product candidates AMP-105, instead of AMP-107 as originally contemplated in the Contract Research Agreement. The total cost of the Contract Research Agreement will be increased by approximately $0.6 million, which reflects the additional work that Hanxin will need to perform and compensation to Hanxin for the work already provided for AMP-107.

​

During the three months ended March 31, 2026 and 2025, the Company paid an immaterial amount under this agreement. As of March 31, 2026 and December 31, 2025, the Company had an immaterial amount of payable to Hanxin under this agreement.

​

Supply Agreement with Letop

​

In November 2022, the Company entered into a supply agreement with Nanjing Letop Biotechnology Co., Ltd., or Letop, which is considered a related party due to an ownership stake of Henry Zhang. Under the terms of the supply agreement, Letop will manufacture and deliver chemical intermediates to the Company on a cost-plus basis. This agreement expired in the fourth quarter of 2025.

​

In March 2026, the Company entered into a new supply agreement with Letop, whereby Letop will manufacture and deliver chemical intermediates to the Company on a cost-plus basis. The agreement is effective for five years.

​

During the three months ended March 31, 2026 and 2025, the Company paid an immaterial amount under this agreement. As of March 31, 2026 and December 31, 2025, the Company did not have any additional accruals payable to Letop.

​

Primatene MIST^® Distribution Agreement with Hong Kong Genreach Limited

​

In August 2024, the Company entered into a distribution agreement with Hong Kong Genreach Limited, or Genreach, a wholly owned subsidiary of Hanxin, a related party. Per the terms of the agreement, the Company has appointed Genreach as the exclusive distributor to market and sell Primatene MIST^® in Mainland China, Taiwan, Hong Kong, and Macau in the Greater China region. Genreach will be responsible for obtaining any and all regulatory approvals in the region for Primatene MIST^®.

​

In January 2026, the Company and Genreach amended the distribution agreement to expand the region of the distribution agreement to include the Middle East countries and Southeast Asia, as well as amending the annual minimum purchase

amount.

​

The term of the agreement is for ten years, with both parties having termination rights without cause after the completion of the second contract year.

​

During the three months ended March 31, 2026 and 2025, the Company did not recognize any revenue from the distribution agreement with Genreach. As of March 31, 2026 and December 31, 2025, the Company did not have any receivables from Genreach.

​

BAQSIMI^® Distribution Agreement with Nanjing Chengong Pharmaceutical Co., Limited.

​

In October 2025, the Company entered into a distribution agreement with Nanjing Chengong Pharmaceutical Co., Limited, or Chengong, a wholly-owned subsidiary of Hanxin, a related party. Per the terms of the agreement, the Company will collaborate with Chengong to expand distribution of BAQSIMI^®, in Mainland China, Taiwan, Hong Kong, and Macau in the Greater China region, and appoint Chengong as the exclusive distributor to market and sell BAQSIMI^® in the Greater China Region. Chengong is responsible for obtaining any and all regulatory approvals in the Region, and performing the required post marketing clinical trials for BAQSIMI^®.

​

The term of the agreement is for ten years, with both parties having termination rights without cause after the completion

of the fourth contract year.

​

During the three months ended March 31, 2026, the Company did not recognize any revenue from the distribution agreement. As of March 31, 2026, the Company did not have any receivables from Chengong.