[ESMO 2026] Lecrentia Combination Therapy Controls Skin Toxicity via 'Upfront Administration'... Management Strategy to Reduce Treatment Discontinuation

At the European Society for Medical Oncology (ESMO 2026), held in Madrid, Spain, from October 23 to 26, 2026, important clinical data on the treatment of EGFR-mutant non-small cell lung cancer was unveiled. A research team led by Professor Byung-Chul Cho of Yonsei Cancer Center presented the results of a new cohort in the 'COCOON Study' ¹, which demonstrated an effective management strategy for cutaneous adverse events associated with the combination therapy of Rybrevant SC (Subcutaneous) and Lazcluze (lazertinib).

The core finding of this study is the provision of clinical evidence showing that simply adjusting the sequence of drug initiation can significantly reduce skin toxicity and prevent treatment discontinuation. Specifically, the 'lead-in' administration approach, where Lazcluze is administered first followed by the addition of Rybrevant, was confirmed to lower the risk of cutaneous side effects while maintaining anti-tumor activity ¹. This presents a direction for simplifying complex adverse event management protocols while improving actual treatment persistence rates.

Balancing Cutaneous Toxicity Management and Maintenance of Anti-Tumor Activity

Cutaneous adverse events are among the primary causes of treatment discontinuation in combination therapies. The COCOON Study was designed to verify the efficacy and safety of Lazcluze lead-in administration to address this issue. The study was divided into two cohorts, both of which applied the same simplified cutaneous prophylactic regimen.

This prophylactic regimen consists of three main components: oral tetracycline-class antibiotics, ceramide-based moisturizers, and oral zinc gluconate supplements ¹. Previously complex enhanced prophylactic regimens were simplified into this three-component combination.

The difference between the two cohorts lies in the 'timing' of drug initiation. The standard administration cohort comprised 70 patients who received the two drugs simultaneously or in a predetermined sequence according to the protocol. In contrast, the Lazcluze lead-in administration cohort consisted of 34 patients who started Lazcluze first and added Rybrevant after a certain period ¹.

Changes in the Incidence of Cutaneous Adverse Events Brought About by 'Lead-in Administration'

The difference in skin toxicity based on administration timing was starkly revealed in the incidence rates within 12 weeks. The incidence of Grade ≥2 cutaneous adverse events within 12 weeks of treatment initiation was 39% in the standard administration cohort. In contrast, the incidence dropped to approximately half or less, at 18%, in the Lazcluze lead-in administration cohort ¹.

These results are highly significant even when compared to the incidence rate (42%) observed with enhanced prophylactic regimens in existing intravenous combination therapies. The standard administration cohort maintained a level (39%) similar to that seen with enhanced prophylaxis, while the lead-in administration cohort recorded an even more improved figure (18%) than the results with enhanced prophylaxis ¹.

A particularly noteworthy point is the difference in drug continuation. In the Lazcluze lead-in administration cohort, there were no patients who temporarily or permanently discontinued Rybrevant due to cutaneous adverse events ¹. Professor Byung-Chul Cho explained that such adjustments to the drug initiation schedule could contribute to patients' long-term treatment persistence ¹.

(Source: New cohort results from the COCOON Study ¹)

Anti-Tumor Activity Was Not Impaired

Treatment strategies aimed at reducing side effects often raise concerns among clinicians due to the potential for decreased anti-tumor activity. However, according to COCOON Study data, it was confirmed that there was no loss of treatment efficacy even when the Lazcluze lead-in administration approach was applied.

Looking at the Investigator-Assessed Objective Response Rate (ORR), the standard administration cohort recorded approximately 71%. The Lazcluze lead-in administration cohort recorded approximately 70% ¹. High response rates were observed in both cohorts, and no significant impairment in anti-tumor activity due to lead-in administration was observed.

In other words, this suggests that while the risk during the critical first 12 weeks, when skin toxicity is most severe, is mitigated by Lazcluze monotherapy, the full therapeutic benefit from the subsequently added Rybrevant can still be realized. This represents a clinical advantage that allows for the management of patient quality of life while maintaining treatment continuity.

Implications for Management Strategies Expected in Actual Clinical Practice

The COCOON Study demonstrates how flexibly side effect prevention protocols can be designed in lung cancer treatment. While the three basic elements—tetracycline-class antibiotics, ceramide moisturizers, and zinc gluconate supplements—play an essential role in cutaneous toxicity management, the addition of the 'administration sequence' variable significantly lowers the incidence of side effects.

In particular, the results from the Lazcluze lead-in administration cohort, where no patients discontinued Rybrevant [¹], prove that 'drug initiation timing' can be a highly effective strategic tool in clinical settings where cutaneous side effects are a major barrier to treatment continuation.

The data presented at ESMO 2026 offers a realistic management approach that adjusts the cutaneous toxicity issue, previously cited as a limitation of existing combination therapies, to a manageable level while simultaneously maintaining therapeutic efficacy for tumor control. This emphasizes that clinicians should consider administration schedules and sequences as key factors when establishing patient-specific adverse event management strategies ¹.