Tarsus Pharmaceuticals has dosed the first participant in its Phase 2 Calliope trial of TP-05, an investigational oral therapy aimed at preventing Lyme disease in approximately 700 at-risk adults across endemic US regions. The programme targets a significant unmet need as a potential first-in-class, non-vaccine prophylactic for Lyme disease, where no FDA-approved preventive drugs currently exist. Whilst the trial marks progress, near-term investment focus remains on XDEMVY adoption and margins. The company recently received a $15 million milestone payment tied to TP-03 approval in China, highlighting monetisation of its lotilaner platform beyond the US. Analyst projections for Tarsus vary widely, with some forecasting $847 million revenue and $237 million earnings by 2028, whilst more cautious estimates suggest $988 million revenue and $188 million earnings by 2029.

Dianne Whitfield, Chief Human Resources Officer at Tarsus Pharmaceuticals, sold 12,274 shares of common stock worth approximately $839,000 between 17 and 19 March 2026. The sale represented 25.95% of her direct holdings, reducing her position from 47,302 to 35,028 shares. The transaction was a mandatory "sell to cover" arrangement tied to RSU vesting for tax withholding purposes, rather than a discretionary sale. Shares sold at a weighted average price of $68.36. Tarsus Pharmaceuticals generated $451.4 million in net product sales in 2025, more than doubling from the prior year, driven by adoption of its lead product XDEMVY. The company narrowed its net loss to $66.4 million and ended 2025 with over $417 million in cash and marketable securities.