Merck Advances Wet AMD Drug Trial Amid Keytruda-Focused Bridge Year

What happened

Merck announced the initiation of a pivotal Phase 2b/3 trial for MK-8748 (Tiespectus), a bispecific Tie2 agonist/VEGF inhibitor targeting neovascular age-related macular degeneration (wet AMD). This move aligns with the company's broader strategy, highlighted in the DeepValue report, to diversify its pipeline as it faces impending loss-of-exclusivity (LOE) events for drugs like Januvia and Bridion in 2026. However, the trial is in early stages and represents a non-oncology asset, which may not immediately address the core investor concern of Keytruda concentration, accounting for 49% of 2025 sales. The DeepValue report emphasizes that Merck's near-term narrative is tied to executing its 2026 bridge year, with sales guided to $65.5B–$67.0B and significant acquisition charges expected. Thus, while this announcement shows pipeline activity, it does little to shift the market's focus from near-term financial metrics and Keytruda's performance.

Implication

In the short term, this trial is unlikely to impact revenue or earnings, as it is in Phase 2b/3 and will require years for potential commercialization. It demonstrates Merck's efforts to expand beyond oncology, which could help mitigate long-term concentration risk if successful. However, the DeepValue report stresses that investor confidence hinges on visible progress in oncology, such as subcutaneous Keytruda uptake, and managing 2026 LOE declines and acquisition charges. Large charges from deals like Cidara and reported Terns acquisitions could overshadow pipeline news, anchoring the stock to lower multiples. Therefore, while this adds optionality, it does not change the immediate investment thesis centered on 2026 execution and charge containment.

Thesis delta

This announcement does not materially shift the investment thesis, as it represents incremental pipeline progress in a non-core therapeutic area. The core thesis remains focused on Keytruda's growth, the absorption of 2026 LOE headwinds, and managing acquisition-related charges over the next 6-9 months. Investors should continue to monitor near-term catalysts and financial metrics rather than early-stage pipeline additions.