Tafenoquine for Relapsing Babesia: When Standard Treatment Fails
Relapsing Babesia may persist despite standard treatment
Drug resistance and co-infections can complicate recovery
Tafenoquine is being explored in difficult Babesia cases
Relapsing Babesia can occur when standard treatment fails to fully eradicate infection, particularly in immunocompromised patients or individuals with resistant disease.
Some patients continue to experience fatigue, sweats, dizziness, air hunger, cognitive symptoms, or recurrent fevers despite multiple courses of therapy.
Tafenoquine is an antimalarial medication being explored as a possible treatment option in difficult Babesia cases.
For a broader overview of symptoms, testing, and treatment approaches, visit our Babesia and Lyme disease guide.
A Relapsing Babesia Case With Treatment Resistance
A 36-year-old man was hospitalized in 2019 after experiencing unexplained fevers for two weeks. He was later diagnosed with Babesia with 8.5% parasitemia.
The patient had a history of granulomatosis with polyangiitis and was immunocompromised following rituximab therapy. He had also previously received methotrexate, cyclophosphamide, and steroids.
Initial Babesia treatment included atovaquone and azithromycin for 10 days. However, the atovaquone dosage was lower than standard twice-daily dosing.
Two months later, the patient relapsed and again tested positive for Babesia on blood smear.
He underwent additional prolonged courses of azithromycin and atovaquone but continued to relapse.
Evidence of Drug-Resistant Babesia
After repeated relapses, testing demonstrated at least partial genetic resistance to both azithromycin and atovaquone.
The physicians then escalated treatment to a four-drug regimen including:
- Malarone®
- high-dose azithromycin
- clindamycin
- additional atovaquone
Despite aggressive treatment, the patient remained ill.
Tafenoquine for Babesia
The patient was eventually treated with a six-week course of tafenoquine alone.
Tafenoquine is an 8-aminoquinoline antimalarial medication approved for malaria prophylaxis and prevention of relapse of Plasmodium vivax malaria.
Animal studies have demonstrated that tafenoquine may rapidly clear Babesia microti infection, including in highly immunocompromised mice.
Before starting tafenoquine, clinicians confirmed that the patient did not have:
- glucose-6-phosphate dehydrogenase (G6PD) deficiency
- a significant psychiatric history
- QT interval abnormalities
The patient ultimately improved following tafenoquine therapy, although investigators acknowledged that they could not determine whether the response resulted solely from tafenoquine or from the cumulative effect of prior therapies.
Why Babesia Treatment Sometimes Fails
Babesia treatment failure may occur for several reasons, including:
- drug resistance
- immunosuppression
- delayed diagnosis
- persistent infection
- inadequate treatment duration
- unrecognized co-infections
In clinical practice, some patients with persistent symptoms after Lyme disease treatment are later found to have untreated or relapsing Babesia infection.
Importantly, doxycycline alone does not eradicate Babesia.
Patients with Babesia may continue to experience symptoms such as:
- night sweats
- air hunger
- fatigue
- dizziness
- exercise intolerance
- cognitive dysfunction
Babesia duncani and Difficult-to-Treat Infection
The authors did not address whether the patient may have had Babesia duncani, a species originally identified on the West Coast of the United States but now recognized more broadly.
Some clinicians have observed that Babesia duncani may be more difficult to treat and more likely to relapse in certain patients.
Further research is needed to determine which Babesia species respond best to tafenoquine and other emerging therapies.
Frequently Asked Questions
What is tafenoquine?
Tafenoquine is an antimalarial medication being explored as a potential treatment option for relapsing or resistant Babesia infections.
Can Babesia relapse after treatment?
Yes. Some patients experience recurrent Babesia symptoms or positive blood smears after standard therapy, particularly in cases involving immunosuppression or drug resistance.
Does doxycycline treat Babesia?
No. Doxycycline alone does not eradicate Babesia infection.
What medications are used to treat Babesia?
Common Babesia treatments may include atovaquone, azithromycin, clindamycin, quinine, Malarone®, and in select cases tafenoquine.
Can Babesia become chronic?
Some patients experience persistent or relapsing Babesia symptoms, particularly when diagnosis or treatment is delayed.
What is the difference between Babesia microti and Babesia duncani?
Babesia microti is the most common Babesia species in the northeastern United States, while Babesia duncani has also been associated with difficult-to-treat infections.
Clinical Takeaway
Relapsing Babesia may persist despite standard treatment, particularly in immunocompromised patients or cases involving drug resistance.
Tafenoquine is emerging as a potential option in difficult Babesia infections, although additional research is still needed.
Persistent symptoms after Lyme disease treatment should prompt consideration of Babesia or other untreated co-infections, especially when doxycycline alone was used.
Related Articles
These related articles explore Babesia symptoms, difficult-to-treat infection, co-infections, and persistent symptoms following tick-borne illness.
The Case of an Untreated Babesia Infection
Wide Range of Babesia Symptoms and Presentations
Geriatric Babesia Cases May Require Longer Treatment
Lyme Coinfections
Post-Treatment Lyme Disease Syndrome
References
- Marcos LA, Leung A, Kirkman L, Wormser GP. Use of tafenoquine to treat a patient with relapsing babesiosis with clinical and molecular evidence of resistance to azithromycin and atovaquone. IDCases. 2022;27:e01460.
Dr. Daniel Cameron, MD, MPH
Lyme disease clinician with over 30 years of experience and past president of ILADS.
Symptoms • Testing • Coinfections • Recovery • Pediatric • Prevention
Tested positive to B. Duncani multiple times, treated with many different AB, including ATovaquone, Malarone, for over a year, they symptoms come back as when I go off AB, and only partially resove when on them, I gave up.
There seems to be no protocol on treating Lyme & Babesia or real diagnostic tool to know what I we are suffering from, a bunch of guessing and very expensive too. The LLMD medicine is really a guessing game with a bunch of AB. & herbs / vitamins based on hearsay, also copy and paste of what the famous Dr. Horowitz or Dr. Jemsek may have speculated sometime in the past. LLMD’s are hesitant to go all in on IVIG or intv. AB, leave it up to the patient to run around to convince someone to treat them. They dont even know when to stop, usually ends when the patient has spent all they got and are coming to term with the pain.
Primary care physicians I have seen say it’s one of the following herniated disk, fibro myalgia, sleep apnea, stress, pre diabetic, and when I developed all of this in such a short period of time, I am told we dont know (or dont care)
I have given up hope.
Joel,
Most of us have the same issue with PC.
I can’t even get them to test for other issues. I begged for years and finally got 2 additional tests when I tested positive for qfever. Then the PC said he didn’t know what to do with the results.
Contacted the health department and they referred me back to the same pc.
Of the several people I know with Babesia duncani (including myself) NOT ONE has been able to eradicate it with any combination of drugs and/or herbs.
I think most anti Protozoa drugs are anti cancer drugs when you can benefit from an unfettered search on internet ( as I can from overseas) and dig about forty pages of repeated material ( yawn) in. I’m so glad you’re feeling better. Babesia has something to teach us all quite obviously. My homeopath doctor in Brasilia also uses magnetic resonance and is quite genius. It’s great you study this and are inspired by your recovery.
I am currently using this to treat a very persistent case of Babesia, and I am immune- compromised. What dose did this person take for six weeks?
“3/10/20 he was started on a 6 week regimen of tafenoquine aloneThe dose was 200 mg daily for three consecutive days and then 200 mg per week, i.e., the regimen FDA approved for malaria prophylaxis” wrote the Marcos LA, etc You can read the article on pubmed at https://pmc.ncbi.nlm.nih.gov/articles/PMC8885462/
Is this treatment successful for patients with additional infections symptoms ch as bartonella, Lyme and Rocky Mtn Spotted Fever?
No
I have been on tafenoquine 200mg weekly for 2 years for chronic babesiosis and I do think it worked well for me.
However my son was treated with the same regimen along with atovaquone for 8 months. For acute babesia duncani the dosage should be prescribed differently.
Thank you for sharing your experience. Treatment decisions, including medication choice, dose, and duration, need to be individualized and guided by a treating clinician. I can’t comment on specific regimens in comments.
Good luck trying to get it. I’m too tired to continue trying to track down someone that carries tafenoquine. Pharmacies are not going to help you. Just keep saying it’s on backorder. My doctor is so busy, but I have a call into his office, to see if he can find out how to get it. I have tried all the other anti malaria drugs. None of them helped with Babesia Duncani.
FYI: In the past I tested indeterminate for Lyme, positive for anaplasomosis and ehrlchiosis. They didn’t show up on my last panel. I had been on doxycycline for two years. The test I had in 2019 showed babesia duncani. My doctor ran another panel this past year. It showed the B. Duncani is worse, and didn’t respond to previous treatments, plua I have a different borrelia infection called Borrelia Hermsii.
You’re also right that doxycycline alone is not effective for Babesia, which requires a different approach.
Cases like yours are a reminder that these illnesses are often more complicated than a single infection.
My doctor from Washington state was able to get tafenoquine from a pharmacy in Florida. Good grief. So I’m now living in Wisconsin. I could not find a good or honest LLMD, functional medicine doctor, or LLND in Wisconsin. So I am still being treated based upon my testing from my doctor that I had in Washington. I still can’t believe the shysters here in Wisconsin. I also noticed the people I know in Wisconsin that were able to get proper treatment are all men. I’m starting to see a pattern..