"Effect of Camzyos confirmed in Korean patients with oHCM"

Hyung-Kwan Kim, Professor of Seoul National University's Department of Internal Medicine

Real-World Evidence (RWE) data unveiled for Korean oHCM patients…Effectiveness and safety data secured

Shortness of breath disappeared and a different level of exercise capacity was shown…improved quality of life

Hyung-Kwan Kim, Professor of Seoul National University

"After Camzyos was introduced to Korea, patients with obstructive hypertrophic cardiomyopathy (oHCM) and doctors have high treatment satisfaction.

 

Notably, realworld data showed that Camzyos administration had a comparable effect to confirmatory clinical trial." During a recent meeting with Daily Pharm, Hyung-Kwan Kim, Professor of Seoul National University's Department of Internal Medicine, evaluated that the obstructive hypertrophic cardiomyopathy (oHCM) Camzyos showed a similar level of improving symptom compared to confirmatory clinical trial.

 

oHCM is a condition where the left ventricular muscle abnormally thickens, obstructing the left ventricular outflow tract (LVOT) and preventing the heart from effectively pumping blood.

 

More than 70% of all hypertrophic cardiomyopathy patients have the obstructive form.

 

oHCM's key problem is 'excessive cardiac contractility.' Unlike typical heart failure patients, the hearts of oHCM patients contract excessively.

 

This phenomenon occurs due to an abnormal over-binding of proteins called actin and myosin within the myocardial cells.

 

This leads to excessive left ventricular contraction, blood flow obstruction, and patients experiencing shortness of breath during exercise, chest pain, and fainting.

 

In severe cases, it can lead to heart failure, atrial fibrillation, and sudden death.

 

Professor Kim pointed out, "Until now, treatment involved lowering the heart rate with beta-blockers or calcium channel blockers to alleviate symptoms.

 

If necessary, alcohol septal ablation or surgical myectomy to remove muscle had to be considered.

 

However, these were not treatments that controlled the fundamental mechanism of the disease." BMS's Camzyos is a treatment that works by reducing the excessive cross-bridge formation between actin and myosin within the heart muscle, which is the cause of oHCM.

 

This allows the excessively contracted heart muscle to relax.

 

Additionally, this treatment demonstrated a myocardial remodeling effect, improving not only the heart's function but also its structure.

 

In December 2024, Camzyos received national health insurance reimbursement in Korea.

 

This means that patients with oHCM in Korea now have access to a targeted treatment option other than surgery.

 

Many patients are also being treated with Camzyos at Seoul National University Hospital.

 

Professor Kim said, "In the case of a male patient in his 60s who hadn't responded to previous medications, his shortness of breath disappeared within three months of Camzyos administration, and his exercise capacity significantly improved." He added, "His quality of life reached a completely different level." 1-year Real-World Evidence (RWE) data released for Korean oHCM patients In the EXPLORER-HCM clinical trial, Camzyos significantly improved the primary endpoint, which considered both symptom severity and exercise capacity, compared to the placebo group.

 

Furthermore, Camzyos's efficacy has been confirmed in Korean patients.

 

In March of this year, the first Real-World Evidence (RWE) study results on the effectiveness and safety of Camzyos over one year in Korean oHCM patients were published.

 

The study showed that in 46 symptomatic (NYHA class II-III) oHCM patients in Korea who received Camzyos, more than half (58.1%) experienced an improvement of at least one NYHA class.

 

LVOT pressure gradients also decreased to 40.1 mmHg at rest and 68.1 mmHg during the Valsalva maneuver (a breathing technique of holding one's breath and applying pressure to the chest in a specific way).

 

Significant improvements were also demonstrated in cardiac hypertrophy-related indicators such as left ventricular wall thickness and left atrial volume.

 

This study holds significant meaning as it is the first to evaluate Camzyos's RWE not only in Korea but across Asia.

 

Professor Kim stated, "Camzyos demonstrated an effect in the domestic clinical setting comparable to what was confirmed in its previous confirmatory clinical trials, and no concerning adverse reactions were observed.

 

It is particularly impressive that despite Korean patients having higher clinical severity, with greater LVOT pressure gradients than participants in the global confirmatory trial, the domestic real-world data showed almost the same level of efficacy as the confirmatory clinical trial." Professor Kim added, "Concerns have been raised that Asian patients might have a higher risk of adverse reactions or require lower doses during Camzyos treatment due to lower activity of the CYP2C19 enzyme involved in drug metabolism compared to Western patients.

 

This RWE study has alleviated such concerns." Another notable finding from this study is the confirmation that N-terminal pro-brain natriuretic peptide (NT-proBNP) levels alone can be used to monitor the treatment response to Camzyos.

 

NT-proBNP is a biomarker used to assess the severity of heart failure and determine prognosis, increasing when myocardial cells in heart failure patients experience excessive load, such as ventricular stretching.

 

According to Professor Kim, in the U.S.

 

and Europe, patients must undergo echocardiography monthly for the first three months of Camzyos administration, and then every three months thereafter, posing a somewhat burdensome follow-up management process.

 

However, Professor Kim explained that this RWE study confirmed that changes in NT-proBNP levels could be easily monitored through blood tests, without echocardiography, to assess LVOT pressure gradient reduction and Camzyos treatment response.

 

Professor Kim evaluated, "We are currently preparing follow-up data for a larger number of patients, and a trend of approximately 1-2 mm reduction in left ventricular thickness and improvement in diastolic function is being observed after Camzyos treatment.

 

Both medical professionals and patients who have experienced Camzyos treatment are showing high satisfaction." Camzyos efficacy proven..."More patient pool required" Despite the emergence of targeted treatment options like Camzyos, diagnosing oHCM remains challenging.

 

According to Professor Kim, while approximately 70% of all HCM patients in the U.S.

 

are diagnosed with oHCM, the proportion of oHCM patients in Korea is low, at around 20%.

 

Professor Kim stated, "I believe that the low oHCM diagnosis rate is partly due to the lack of active utilization of exercise stress tests and echocardiography.

 

For instance, many patients show no particular abnormalities or symptoms at rest, but significant issues are discovered during exercise stress tests or echocardiography." Furthermore, "I anticipate that a considerable number of patients currently diagnosed with non-obstructive HCM could be reclassified as oHCM if additional exercise stress tests or echocardiography are performed.

 

Therefore, I believe there is an absolute need for national-level awareness campaigns and public relations regarding the necessity of exercise stress tests and echocardiography." oHCM patients who experience persistent symptoms such as shortness of breath or chest pain tend to increasingly avoid exercise.

 

This leads to a higher risk of developing various complications as they age, including adult diseases like obesity, diabetes, and hypertension, as well as coronary artery disease.

 

Professor Kim said, "If Camzyos is administered early to these patients, improving their symptoms and restoring their condition to a level where exercise is possible, it can help prevent weight gain and other complications.

 

I believe this contributes not only to the individual patient's health but also, in the long term, to reducing indirect healthcare expenditures caused by HCM on the national health insurance finances." Professor Kim stressed, "Since the introduction of Camzyos, patients' symptom control has become stable, and the approach to HCM treatment in Korea is gradually changing.

 

Based on actual clinical experience, all patients treated with Camzyos have shown symptom improvement, so I believe Camzyos can establish itself as an option to avoid surgery, which is often the last resort." Finally, Professor Kim said, "In conclusion, Camzyos is an option that can provide various direct and indirect benefits to patients, and its role is expected to expand further in the future.

 

In my opinion, I strongly recommend active treatment for patients diagnosed with oHCM who are candidates for Camzyos."