Medicine Matched to You

From tumor biomarkers to treatments made with a patient’s own cells, medicine is learning to respond to individual biology. Bespoke gene editing points toward another frontier.

Mobilized News | October 24, 2026

For an infant named KJ Muldoon, the question was unusually specific: could researchers build a treatment around the genetic change making him seriously ill?

KJ had severe CPS1 deficiency, a rare disorder that disrupts the body’s ability to process ammonia. A team at Children’s Hospital of Philadelphia and Penn Medicine designed a gene-editing treatment targeting his particular mutation. He received his first dose in February 2025. [1]

The case offers a glimpse of medicine becoming personal at the molecular level.

The big idea: Personalized medicine already exists, but it takes several forms.

Sometimes it means matching an existing medicine to a biological feature. Sometimes it means modifying a patient’s own cells. At the experimental frontier, it can mean designing a therapy for a particular person’s genetic variant.

Precision medicine considers genomic information alongside environment, lifestyle and other health information. DNA is one part of the picture. [2]

Why it matters: A diagnosis does not describe every biological difference that affects treatment.

Two people with the same type of cancer can have different changes driving their disease. Biomarker testing can help clinicians select treatments more likely to help and avoid some that are unlikely to work. [3]

Here are three routes already reaching clinical care—and one showing what could come next.

1. Treating a cancer’s biology.

Tumor profiling examines genes, proteins and other markers that can inform treatment.

For example, certain changes in the EGFR gene can identify cancers that may respond to medicines targeting those changes. The National Cancer Institute also supports molecular matching research, including Pediatric MATCH, which studies treatment selection using tumor characteristics. [3]

This is different from testing inherited cancer risk. One investigates features of an existing tumor; the other looks for inherited variants that can increase susceptibility.

A molecular match is not a guarantee. Treatment response can vary, and a cancer’s biology can change over time. [3]

2. Understanding how a person handles a medicine.

Pharmacogenomics examines how genetic differences affect drug response.

The FDA’s Table of Pharmacogenetic Associations identifies gene–drug relationships supported by evidence, including differences in drug metabolism and, in some cases, therapeutic effects or adverse-event risks. [4]

The potential is practical: relevant genetic information can help guide a clinician’s choice of medicine or dose.

The evidence is specific to the gene, drug and clinical situation. The FDA cautions that inclusion in its table does not automatically mean testing is recommended before prescribing, and many listed associations have not been evaluated for improved clinical outcomes from testing. [4]

3. Using a patient’s own cells as treatment.

Casgevy, an FDA-approved therapy for certain patients with sickle cell disease or transfusion-dependent beta-thalassemia, uses a patient’s own blood stem cells, edited outside the body and returned through transplantation. [5,6]

For sickle cell disease, the edits increase fetal hemoglobin, which helps prevent red blood cells from sickling. [6]

The cell source is personal; the treatment platform is shared across eligible patients. This differs from designing a new drug for every individual mutation.

Receiving it involves a demanding transplant process, including conditioning chemotherapy before the edited cells are infused and ongoing monitoring afterward. [6]

The emerging frontier: A treatment designed for one mutation.

KJ’s team, led by physician-scientists Rebecca Ahrens-Nicklas and Kiran Musunuru, developed a CRISPR base-editing therapy delivered to the liver in lipid nanoparticles. [1]

In the initial report published in May 2025, KJ tolerated more dietary protein and needed less medication to remove nitrogen waste. The researchers emphasized the need for longer follow-up. [1]

That demonstrated feasibility in one patient. It did not establish a cure or prove that the approach would work for other disorders.

The next challenge is making such development repeatable: retaining rigorous safety evaluation while adapting a platform to different rare mutations.

The wider picture: Precision also needs access.

Mobilized’s public-interest test is whether these advances improve people’s lives across communities.

That means affordable testing, understandable consent, protection for biological data, representative research and access to treatment when a useful match is found. Measuring more of someone’s biology has limited value if the resulting care remains out of reach.

Prevention belongs in this picture, too. Genetic information should complement attention to nutrition, environmental exposure, living conditions and clinical history.

Three questions can make the promise concrete:

Which biological finding would change this care decision?
Is the proposed treatment established for this situation, or experimental?
What evidence supports the benefit, and what are the practical demands of receiving it?

The opportunity is medicine that understands more about the person receiving care—and a health system capable of using that understanding to help them.