In the sentence extracted from biomedical literature, identify all the chemical entities. The required answer format is the same sentence with HTML <span> tags to mark up specific entities. 
### Entity Markup Guides:
Use <span class="chemical"> to denote a chemical.

### Input Text: The reduction in MSSBP was significantly greater with VAL / HCTZ 320 / 25 mg compared with VAL / HCTZ 160 / 12 . 5 mg ( P < 0 . 002 ) .
### Output Text:
The reduction in MSSBP was significantly greater with <span class="chemical">VAL</span> / <span class="chemical">HCTZ</span> 320 / 25 mg compared with <span class="chemical">VAL</span> / <span class="chemical">HCTZ</span> 160 / 12 . 5 mg ( P < 0 . 002 ) . 