In Vivo CAR-T Therapy explained: The next evolution in cancer treatment

Trial results suggest the promising immune therapy is achievable without its costly lab stage, news welcomed by patients and biotech insiders alike.

CAR-T therapy has already transformed treatment options for thousands of patients with blood cancers, but its complex manufacturing process has limited access and kept costs high.

Now, a new wave of in vivo approaches aims to eliminate one of the biggest barriers to adoption by engineering CAR-T cells directly inside the patient’s body. If successful, this shift could make cell therapies faster, simpler, more scalable and significantly more accessible – potentially reshaping the future of cancer treatment and creating major opportunities across the biotech sector.

The ramarketing review cuts through the headlines to explore the developments shaping life sciences, with a different ramarketing expert each month providing context, commercial perspective and the stories that matter most.

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Introducing June’s sector expert…

Leo Bear-McGuinness, Scientific Content Writer

During his years working in science journalism, Leo reported on a range of topics, from the perils of ultra-processed foods to rumoured, undiscovered galaxies to the revolutionary treatment promises of chimeric antigen receptor (CAR) T cell therapy. He returns to the latter subject now to delve into its latest promising development.

Ten years ago, CAR–T cell therapies were on the verge of being approved in the US to treat several rare blood cancers. Excitement was high. Now, many thousands of successful treatments later, excitement is again building as the therapies look set to evolve, moving from ex vivo to in vivo.

An examination of ex vivo

In ex vivo therapy, T cells are taken from a patient and brought to a lab, where technicians add genetic material that instructs the cells to produce CARs. These CAR-T cells are then administered back into the patient via an IV drip. 

Since 2017, the US Food and Drug Administration (FDA) has approved seven CAR-T therapies that operate via this ex vivo process for the treatment of blood cancers [1]. Thousands of patients have been treated. But thousands of others have not. Indeed, it’s been purported that only two out of 10 blood cancer patients in the US who are eligible for the therapies actually receive them [2]. 

Access can be constrained by several factors, including the limited capacity of treatment centers and the high cost of the treatment itself (one 2024 study calculated the median cost of CAR-T therapy in the US to be $608, 100 [3]).  Patient groups are hopeful, however, that in vivo CAR–T therapies can sidestep these barriers. 

An introduction to in vivo

In theory, in vivo therapy avoids ex vivo’s lab stage (and the associated transit back and forth from the lab) by having the patient’s own body modify its own T cells. A couple of different mechanisms have been proposed to achieve this. Some research groups have opted to use lentivirus vectors, which are standard in ex vivo therapy, to target and inject T cells with CAR-encoding genetic material. Other groups have opted to use lipid nanoparticles to produce the same effect [4].

However, there is still much to evidence before a drug utilising either method can be approved by the FDA. Yet recent studies have yielded encouraging results. Two lentiviral vector studies, one performed by Belgium-based EsoBiotec in collaboration with the China-based Shenzhen Pregene Biopharma, and another conducted by US-based Kelonia Therapeutics, demonstrated tumor clearance in patients with relapsed and refractory multiple myeloma [5]. More recent data from the latter study have even shown a sustained presence of CAR-T cells in the peripheral blood and bone marrow of patients, a persistence exceeding that typically seen with ex vivo therapies and one that could help reduce treatment times for multiple myeloma patients [6].

Increasing in vivo investment

Such findings have led to great excitement, and great investment, within the biotech industry. Only this April, Eli Lilly acquired Kelonia Therapeutics in a deal reportedly worth $7 billion [7]. 

Money is being spent outside of cancer therapy, too, on CAR-T cells’ other great potential: treating autoimmunity. Abbvie recently announced it will part with $2.1 billion to purchase Capstan Therapeutics, Inc. and its in vivo CAR-T therapy candidate drug CPTX2309, which is currently being tested in a Phase 1 trial for the treatment of B cell-mediated autoimmune diseases [8].

For patient groups, the hope is that these kinds of significant investments will help support the research needed to realise the great benefits of in vivo therapies: simpler, faster administration routes that come at a much lower cost than current ex vivo therapies. For biotech companies, the onus is on delivering just that — an outcome that looks more realistic with each new investment.

Stay tuned for more ramarketing review installments – get monthly updates direct to your inbox by signing up for alerts. 

References

1. Blood Cancer United, “FDA Expands CAR T Approval to Include Patients with Rare, Aggressive Type of Non-Hodgkin Lymphoma”. Blood Cancer United, 2026. https://bloodcancerunited.org/resources/newsroom/fda-expands-car-t-approval-include-patients-rare-aggressive-type
2. CAR T Vision, “Executive Summary”. CAR T Vision, 2025. https://cartvision.com/executive-summary/ 
3. Mengyang Di, Kunal C Potnis, et al. “Costs of care during chimeric antigen receptor T-cell therapy in relapsed or refractory B-cell lymphomas.” JNCI Cancer Spectrum. 8.4 (2024)
4. Ang MJY, Metzloff AE, et al. “Lipid nanoparticles for engineering next generation CAR T cell immunotherapy.” Nanoscale Horizons. (2025) 
5. Synapse by patsnap, “EsoBiotec Begins First Patient Dosing in BCMA CAR-T Trial for Multiple Myeloma”. Synapse by patsnap, 2025. https://synapse.patsnap.com/article/esobiotec-begins-first-patient-dosing-in-bcma-car-t-trial-for-multiple-myeloma 
6. Kelonia Therapeutics, “Kelonia Therapeutics Presents Updated First-in-Human Data from Phase 1 inMMyCAR Study of KLN-1010 in vivo BCMA CAR-T Therapy at the 2026 American Society of Clinical Oncology (ASCO) Annual Meeting”. Kelonia Therapeutics, 2026. https://keloniatx.com/kelonia-therapeutics-presents-updated-first-in-human-data-from-phase-1-inmmycar-study-of-kln-1010-in-vivo-bcma-car-t-therapy-at-the-2026-american-society-of-clinical-oncology-asco-annual-meeting/ 
7. Lilly Investors, “Lilly to acquire Kelonia Therapeutics to advance in vivo CAR-T cell therapies”. Lilly Investors, 2026. https://investor.lilly.com/news-releases/news-release-details/lilly-acquire-kelonia-therapeutics-advance-vivo-car-t-cell 
8. Abbvie, “AbbVie to Acquire Capstan Therapeutics, Further Strengthening Commitment to Transforming Patient Care in Immunology”. Abbvie, 2025. https://news.abbvie.com/2025-06-30-AbbVie-to-Acquire-Capstan-Therapeutics,-Further-Strengthening-Commitment-to-Transforming-Patient-Care-in-Immunology