Frequently Asked Questions by Patients

Top Questions:

1. What is the status of the bioartificial kidney?

The implantable bioartificial kidney is under development, and we have not begun clinical trials. We have shown that the main functional components of the device (the hemofilter and the bioreactor) work together as intended in animals using small-scale prototypes. This gives us confidence that it will work in humans once the device is scaled up with enough capacity. This video summarizes our latest progress:

2. When will clinical trials start?

We estimate that the artificial kidney is about 4-5 years away from being ready for clinical trials from a technical perspective. However, we do not yet have all the funding we need (estimated at USD 10 million) to complete the preclinical development, so this timeline could be slower.

3. When will the bioartificial kidney be available for patients?

The artificial kidney must undergo multiple rounds of clinical trials before it is approved by the U.S. Food & Drug Administration (FDA) for widespread use. Our goal is to have a device commercially available by the end of the decade (2030), but again this depends on our funding situation, and it is possible that unanticipated technical challenges could slow us down.

4. Will the artificial kidney be available internationally? Or will international patients have to go to the United States for the procedure?

Once the artificial kidney is approved by the FDA, we will work with international regulatory agencies to make the device available around the world. International approvals will likely be a couple of years behind U.S. approval. It is possible that international patients may be able to travel to the U.S. for the procedure in the meantime, depending on their situation.

5. I am waiting for the implantable bioartificial kidney, but my doctor is recommending that I start dialysis and get on the kidney transplant list. What should I do?

You should always heed the advice of your physician or other qualified health provider. The implantable bioartificial kidney is still under development and is not yet available for patients. Please do not delay any recommended treatments.

6. Will patients with any kind of kidney disease be eligible for the implantable bioartificial kidney?

We cannot say definitively, but we expect that in any case where a kidney transplant is needed, our device will be an option. However, individual situations differ, and future eligibility will always be determined by your health care provider.

7. How much will this device cost? Will it be covered by insurance?

The cost of the artificial kidney will depend on the business and economic climate at the time the device is released on the market. We expect that the device will cost no more than a transplant. We will apply for insurance coverage by both Medicare and commercial insurers once the device is in clinical trials.

Basics: device and function

8.How does the artificial kidney work? How big is it?

The implantable bioartificial kidney is about the size of a coffee cup and consists of two main components that work together to get rid of wastes. First, the hemofilter, or blood filter, processes incoming blood to create “ultrafiltrate” that contains dissolved toxins, sugars, and salts. Second, a bioreactor containing kidney cells processes the ultrafiltrate and concentrates it into “urine,” which is directed to the bladder.

9. Will the artificial kidney work as well as a human kidney?

The artificial kidney is designed to work like the natural kidney, filtering the blood and maintaining the body's fluid balance so that dialysis is not necessary. The first versions of the device will not provide as much kidney function as a transplant or a healthy natural kidney, but enough to keep patients off dialysis. Device performance will improve in later versions with advances in technology.

10. What is the surgery like to implant the device?

The implantation procedure will be similar to kidney transplant surgery and will require a hospital stay and general anesthesia.

11. How long will the device last after implantation? Will it have to be replaced?

The device is meant to be permanent. Current testing and research suggest that the device could operate for many years without failure. If failures occur, the replacement of the filter and/or cells could be done through minimally invasive surgery.

12. How will the filter be cleaned?

The filter will not require cleaning or replacement. A thin biocompatible coating is applied to the filter membrane to help prevent clogging and blood clots. The constant flowing of blood over the coated filter surface also helps keep the membrane free of debris.

13. Will patients still have to take immunosuppressive drugs or blood thinners after implantation? Will there be a risk of blood clots?

No. The pores in the membranes used in the artificial kidney are smaller than the size of immune cells and antibodies. As such, the kidney cells in the bioreactor stay isolated from the patient’s immune system. We also do not expect that patients will need to take blood thinning medications like warfarin. The coatings and geometry of the device are designed to prevent formation of blood clots.

14. Will patients still need Erythropoietin (EPO) injections?

Yes. The type of kidney cell in the bioreactor is different than the cells that secrete erythropoietin, so patients will still need supplemental EPO.

15. What kind of GFR value would you expect to see with the artificial kidney?

We are targeting a glomerular filtration rate (GFR) of 20-30 ml/min with the first version of the artificial kidney. We expect that future versions of the device will provide a higher GFR.

16. Can you still get this device if you still have some level of kidney function, or is this only for patients with end-stage kidney disease (ESKD)?

This device is intended for patients with ESKD, defined as a GFR of 15 ml/min or less. It is possible that eligibility could eventually be broadened to patients not yet in renal failure.

17. Are there any predicted side effects?

Some risks will be similar to those associated with other procedures involving implanted medical devices. These include potential complications like infections, surgical trauma, and scars. We will know more about possible side effects once we begin clinical trials.

18. What is iHemo?

iHemo is the name of the implanted dialysis device we are developing. iHemo uses the implantable bioartificial kidney’s blood filter (hemofilter) to perform hemodialysis inside the body – without requiring needles and without any blood leaving the body. Only dialysate cycles in and out through an external pump using a catheter connection.

You can learn more about iHemo and how it works here:

19. What is the status of preclinical testing?

Over the past 15 years, the project has progressed from establishing the scientific foundations and technical methods to showing that the device’s key mechanisms work in animals. Recently, a small-scale prototype was implanted into a pig and successfully produced urine over 3 days. We are iteratively refining our device design to create prototypes that will have the capacity to treat human patients for extended periods.

20. Where can I find updates regarding the progress of the project?

Our Facebook page is a great place to stay informed about our progress. You can also follow us on Instagram, YouTube, LinkedIn, and Twitter.

Facebook: @ArtificialKidney

Instagram: @ArtificialKidney⁠

YouTube: @TheKidneyProject

LinkedIn: The Kidney Project

X: @KidneyProject⁠

We are also starting up a newsletter! To get updates sent straight to your email, sign up here.⁠


21. What kind of federal funding do you receive?

The Kidney Project has been awarded grants from the National Institutes of Health (NIH), National Aeronautics and Space Administration (NASA), National Science Foundation (NSF), and Department of Defense (DOD). We have also received funding from the Kidney Innovation Accelerator (KidneyX), a public-private partnership between the U.S. Department of Health and Human Services (HHS) and the American Society of Nephrology (ASN) launched in 2018.

22. How much funding does The Kidney Project need to complete its work?

We estimate that we need roughly USD 10 million over the next 3-4 years to complete preclinical development of the implantable bioartificial kidney and request approval for human studies. If the funding goals are not met, the timeline for the completion of the device could be extended. 

It is critical that we secure larger funding commitments that will allow us to take the necessary steps necessary to scale up our device for human clinical trials. Once we reach the clinical trial stage, we are optimistic that support from private investors and industry partners will enable us to complete the commercialization process. 

23. How can I make a donation?


Make a gift.


  1. Make checks payable to UCSF Foundation.
  2. Include allocation instructions on the memo line: The Kidney Project.
  3. Send gifts by U.S. Mail to:

    P.O. Box 45339
    San Francisco, CA 94145-0339


Call toll-free 877-499-UCSF (877-499-8273) to charge by phone.

Clinical Trials

24. Do you have a waitlist for clinical trials? How do I sign up?

We are still a few years away from beginning clinical trials and do not maintain a waitlist. If you are interested in being notified once our trials do start enrolling, please complete this form to submit your information to our database:

Please note that the interest list does not guarantee anyone’s participation. It only means that you will be notified when enrollment has opened. It is not necessary to be on the list to be considered. We will announce trial openings via and our social media pages once we are ready to begin enrollment.

25. What are the criteria for choosing the first group of clinical trials patients? Who decides who will participate?

Patient selection for trials will be based on the trial inclusion criteria, which will be developed by our clinical team and reviewed and approved by the FDA and our Institutional Review Board (IRB). Specific patient selection criteria have not been determined at this time.

26. If I donate, will that increase my chances of participation?

While donations are appreciated and serve a vital role in our work, donations have absolutely no influence on selection for trials. This is to protect the integrity of our research and ensure that all participant decisions are made for medically and scientifically sound reasons.

27. Where will the clinical trials take place?

The first clinical trial will mostly likely take place at either UCSF Medical Center (San Francisco, California) or Vanderbilt University Medical Center (Nashville, Tennessee), because this is where The Kidney Project’s leadership is located. Further trials will take place at multiple locations within the United States. The specific institutions are not known at this time.

28. Will international patients be considered?

International patients will certainly be considered. However, due to the study logistics and the need for long-term follow-up, it is likely that most participants will be based in the United States.


Last updated on February 16, 2024.