Menin inhibitors achieve high rates of MRD-negative remissions. However, the median duration is very short (4-6 months), suggesting current MRD assays may not adequately capture residual disease and that "MRD negativity" is not a reliable predictor of long-term benefit for this drug class.
After observing deep, MRD-negative responses at their starting dose, Colonia Therapeutics unconventionally tested a lower dose level. This counter-intuitive strategy aims to identify the minimum effective dose, which is crucial for maximizing the safety profile (the therapeutic window) and improving commercial viability through lower manufacturing costs.
The FLAG-IDA plus venetoclax regimen achieves very high MRD-negative remission rates. However, its similar efficacy in both frontline and first salvage settings suggests it might be more strategically deployed as a salvage therapy, avoiding its high toxicity in all patients upfront.
The company reports 'overall MMR,' which includes patients maintaining a prior response—a less rigorous metric than 'MMR achievement' (new responses). The CEO notes that discerning investors are focused on the latter, more challenging endpoint, revealing a key area of due diligence for the company's impressive data.
The IDH1 inhibitor olutasidenib demonstrates a much longer duration of response than ivosidenib. One hypothesis is that olutasidenib's weaker affinity for wild-type IDH1 makes it a more selective inhibitor of the mutant protein, leading to more durable disease control.
For patients with oligometastatic disease who achieve a deep PSA response (e.g., to zero), oncologists consider finite treatment durations (e.g., 18-24 months) followed by observation. This "do less harm" approach challenges the standard of continuous therapy until progression, aiming for long-term treatment-free intervals.
Initial studies combining menin inhibitors with venetoclax/azacitidine showed high remission rates but also high mortality. Using each agent at its full, 28-day dose caused severe, fatal myelosuppression, forcing protocol amendments to shorten drug exposure to manage toxicity.
The differentiation syndrome with menin inhibitors can be far more severe than with other agents, manifesting as a life-threatening, HLH-like state with massive inflammatory marker elevation (e.g., ferritin >300,000) that may be unresponsive to high-dose steroids.
The failure of the Checkmate 914 adjuvant trial, which used a six-month duration of nivolumab plus ipilimumab, suggests this shorter treatment window may be inadequate. In contrast to positive trials with one year of therapy, this outcome indicates that treatment duration is a critical variable for achieving a disease-free survival benefit in the adjuvant RCC setting.
Experts warn against over-interpreting a single negative ctDNA test after surgery, clarifying that these patients still face a significant 25-30% risk of recurrence. The biomarker's true prognostic power comes from serial testing that shows a patient remains persistently negative over time.
The interpretation of ctDNA is context-dependent. Unlike in the adjuvant setting, in the neoadjuvant setting, remaining ctDNA positive post-treatment signifies that the current therapy has failed. These high-risk patients need a different therapeutic approach, not an extension of the ineffective one.