|  | Dated: , 2019 |  |  | 
               By Order of the Board of Directors,  
             | 
             | 
|  |  |  |  |  | |
|  |  |  |  | Manuel Litchman, M.D.  President and Chief Executive Officer  | 
             | 
|  |  |  | 
               Common Stock  
            Beneficially Owned  | 
             | |||||||||
| 
               Name and Address of Beneficial Owner(1) 
             | 
             |  | 
               Number of  
            Shares and Nature of Beneficial Ownership  | 
             |  | 
               Percentage of  
            Total Common Stock  | 
             | ||||||
| 
               Michael S. Weiss  
             | 
             |  |  |  | 533,158(2) |  |  |  |  |  | 1.3% |  |  | 
| 
               Manuel Litchman, M.D.  
             | 
             |  |  |  | 320,969 |  |  |  |  |  | 0.8% |  |  | 
| 
               Brian Achenbach  
             | 
             |  |  |  | 18,750 |  |  |  |  |  | <1% |  |  | 
| 
               Lindsay A. Rosenwald, M.D.  
             | 
             |  |  |  | 583,158(2) |  |  |  |  |  | 1.4% |  |  | 
| 
               Neil Herskowitz  
             | 
             |  |  |  | 84,158 |  |  |  |  |  | <1% |  |  | 
| 
               Adam J. Chill  
             | 
             |  |  |  | 76,158 |  |  |  |  |  | <1% |  |  | 
| 
               Michael J. Zelefsky  
             | 
             |  |  |  | 73,158 |  |  |  |  |  | <1% |  |  | 
| 
               All executive officers and directors as a group  
             | 
             |  |  |  | 689,509(3) |  |  |  |  |  | 1.7% |  |  | 
| 5% or Greater Stockholders: |  |  |  | ||||||||||
| 
               Fortress Biotech, Inc.  
             | 
             |  |  |  | 11,870,354(4) |  |  |  |  |  | 30.0%(4) |  |  | 
|  |  |  | 
               Class A Common Stock  
            Beneficially Owned  | 
             | |||||||||
| 
               Name and Address of Beneficial Owner(1) 
             | 
             |  | 
               Number of  
            Shares and Nature of Beneficial Ownership  | 
             |  | 
               Percentage of  
            Total Class A Common Stock  | 
             | ||||||
| 
               City of Hope  
             | 
             |  |  |  | 862,392 |  |  |  |  |  | 100.0% |  |  | 
|  |  |  | 
               Class A Preferred Stock  
            Beneficially Owned  | 
             | |||||||||
| 
               Name and Address of Beneficial Owner(1) 
             | 
             |  | 
               Number of  
            Shares and Nature of Beneficial Ownership  | 
             |  | 
               Percentage of  
            Total Class A Preferred Stock  | 
             | ||||||
| 
               Fortress Biotech, Inc.  
             | 
             |  |  |  | 250,000 |  |  |  |  |  | 100.0% |  |  | 
|  |  |  |  | MUSTANG BIO, INC. |  | |||
|  |  |  |  | By: |  |  |  | |
|  |  |  |  |  |  |  | Name: Manuel Litchman, M.D.  Title: President and Chief Executive Officer  | 
             |