Exhibit 99.19
JOINT FILING AGREEMENT
In accordance with Rule 13d-1(k) under the Securities Exchange Act of 1934, as amended, each of the undersigned hereby agrees to the joint filing on behalf of each of them of a statement on Schedule 13D (including amendments thereto) with respect to the ordinary shares, par value US$0.0002 per share of LakeShore Biopharma Co., Ltd, and that this Agreement be included as an Exhibit to such joint filing. Each of the undersigned acknowledges that each shall be responsible for the timely filing of any statement (including amendments) on Schedule 13D, and for the completeness and accuracy of the information concerning such party contained therein, but shall not be responsible for the completeness and accuracy of the information concerning the other persons making such filings, except to the extent that such party knows or has reason to believe that such information is inaccurate.
This Agreement may be executed in any number of counterparts, each of which shall be deemed to be an original, but all of which taken together shall constitute one and the same instrument.
IN WITNESS WHEREOF, the undersigned hereby execute this Agreement as of April 29, 2026.
| Xue Huaqin | By: | /s/ Huaqin Xue |
| Name: Huaqin Xue | ||
| Crystal Peak Holdings Inc. | By: | /s/ Huaqin Xue |
| Name: Huaqin Xue | ||
| Title: Director | ||
| Crystal Peak Investment Inc. | By: | /s/ Huaqin Xue |
| Name: Huaqin Xue | ||
| Title: Director | ||
| Dave Liguang Chenn | By: | /s/ Dave Liguang Chenn |
| Name: Dave Liguang Chenn | ||
| Oceanpine Investment Fund II LP | By: | /s/ Dave Liguang Chenn |
| Name: Dave Liguang Chenn | ||
| Title: Director | ||
| Oceanpine Capital Inc. | By: | /s/ Jiayu Yang |
| Name: Jiayu Yang | ||
| Title: Director | ||
| Adjuvant Capital Management, L.L.C. | By: | /s/ Kabeer Aziz |
| Name: Kabeer Aziz | ||
| Title: Vice President & Secretary | ||
| Adjuvant Capital GP, L.P. | By: | /s/ Kabeer Aziz |
| by its general partner Adjuvant Capital Management, LLC | Name: Kabeer Aziz | |
| Title: Vice President & Secretary | ||
| Adjuvant Global Health Technology Fund, L.P. | By: | /s/ Kabeer Aziz |
| by its general partner Adjuvant Capital GP, L.P. by its general partner Adjuvant Capital Management, LLC | Name: Kabeer Aziz | |
| Title: Vice President & Secretary | ||
| Adjuvant Global Health Technology Fund DE, L.P. | By: | /s/ Kabeer Aziz |
| by its general partner Adjuvant Capital GP, L.P. by its general partner Adjuvant Capital Management, LLC | Name: Kabeer Aziz | |
| Title: Vice President & Secretary | ||
| MSA Growth Fund II, L.P. | By: | /s/ Yu (Jenny) Zeng |
| By: MSA China Growth Fund II GP, LLC, its general partner | Name: Yu (Jenny) Zeng | |
| Title: Managing Partner | ||
| MSA China Growth Fund II GP, LLC | By: | /s/ Yu (Jenny) Zeng |
| Name: Yu (Jenny) Zeng | ||
| Title: Manager | ||
| Superstring Capital Master Fund LP | By: | /s/ Ting Guo |
| By: Superstring Capital Fund GP LLC, its general partner | Name: Ting Guo | |
| Title: General Partner | ||
| Superstring Capital Management LP | By: | /s/ Ting Guo |
| Name: Ting Guo | ||
| Title: Managing Partner | ||
| Epiphron Capital (Hong Kong) Limited | By: | /s/ Sherry Xiaoyu Liu |
| Name: Sherry Xiaoyu Liu | ||
| Title: Director | ||