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: A clinical trial was initiated to evaluate the recommended dose of cyclophosphamide in combination with bortezomib and dexamethasone as induction treatment before stem cell transplantation for younger patients with newly diagnosed multiple myeloma ( MM ) .
### Output Text:
A clinical trial was initiated to evaluate the recommended dose of <span class="chemical">cyclophosphamide</span> in combination with <span class="chemical">bortezomib</span> and <span class="chemical">dexamethasone</span> as induction treatment before stem cell transplantation for younger patients with newly diagnosed multiple myeloma ( MM ) . 