A Study of JNJ-88549968 for the Treatment of Calreticulin (CALR)-Mutated Myeloproliferative Neoplasms

To be considered for this study, you need to be an adult, aged 18 or over. A key requirement is that your essential thrombocythemia (ET) or myelofibrosis (MF) must be linked to a specific change in your CALR gene. Your doctor will need to confirm this.

You also need to be broadly well enough to take part. This means your general health and fitness levels, as assessed by a quick grading system (ECOG), should be 2 or below. There are also specific criteria related to the risk level of your ET or MF that your study doctor will check.

There are also some reasons why you might not be able to join. For example, if you have certain allergies, other cancers that are active or were recently treated (with some exceptions like certain skin cancers), or if you've recently had a solid organ transplant or a stem cell transplant. Also, serious heart conditions within the last six months would prevent participation. Your study doctor will go through all these details with you carefully.

If you decide to take part in this study, you'll be given the new study medicine, JNJ-88549968. In some cases, you might also receive it alongside other existing treatments like ruxolitinib or momelotinib. You'll have regular visits to the clinic so the study team can monitor your health and how you respond to the treatment. This will involve regular check-ups, blood tests, and other assessments.

The study is divided into two main parts. The first part focuses on finding the safest and most suitable dose of JNJ-88549968. Once that dose is identified, the second part will involve more people receiving that specific dose to further assess its safety and how effectively it works. The total duration of your participation will vary depending on which part of the study you are in and how you respond, but the study team will be able to give you a clearer idea of the expected time commitment, including follow-up appointments.