“Stepping into Dr. Kleef’s office was like entering a spa. After being labeled as a number for months I finally was treated like a human being.”

Diana Wright
Stage IV Patient

A clip from Dr. Diana’s movie, The Unbelievable Plight of Mrs. Wright, describing her first interaction with Dr. Kleef.

Diana receiving targeted treatments in 2012
Diana receiving hyperthermia treatment in 2012

Meet the Doctor that Saved My Life

Dr. Ralf Kleef

Click here to visit Dr. Kleef’s website

Dr. Kleef’s Clinic

Book an Appointment with Dr. Kleef
  1. Please send us an e-mail to [email protected] including all your latest findings. If your documents are large file sizes, feel free to send in multiple emails. We are also happy to receive a Dropbox link.
  2. We will schedule a Skype conversation with Dr. Ralf Kleef.
  3. Our patient management team will inform you about treatments and cost within a short time.

Please note that if you do not receive an answer within the next business day, please resend your email and/or give us a call. Sometimes emails are blocked by spam filters.

Dr. Ralf Kleef is both an MD and ND who received his state examination in medicine at the University of Witten-Herdecke, Germany in 1991.

With his training in immunology at Memorial Sloan Kettering Cancer Centre in NYC and later at the NIH, Office of Alternative Medicine (OAM), in 1996 he found his passion: treating cancer through immunotherapy in the footsteps of the father of cancer immunotherapy, William B. Coley.

Dr. Kleef developed a unique cancer treatment from his growing wealth of experience and knowledge through a custom-tailored combination of fever therapy, hyperthermia, and checkpoint inhibitors. In his treatments, he observed that the side effects of immunotherapy (immune-related adverse effects) occur in much lesser degrees of intensity. Therefore, he believes that this is a safe protocol and is easily tolerable for patients.

Dr. Ralf Kleef featured in Diana’s documentary, The Unbelievable Plight of Mrs. Wright


Where is your clinic and how do I get to it?

Our clinic in Vienna has moved to the beautiful and modern city of Budapest, capital of Hungary. At our new home we are establishing a healing center where we will be able to provide our treatments and services to our patients at even a higher level and for greater comfort. We will offer even more services locally.  A new, one of the most modern, effective, patient-compliant and flexibly applicable hyperthermia department in the world will await those who choose to recover in our new clinic.

Where can I stay during treatment?

We can send you more information about accommodation close to our clinic if you contact us.

Do you accept U.S. health insurance?

Dr. Kleef Immunotherapy and Integrative Oncology is a private-billing outpatient clinic. We will provide all the information needed so you can submit paid bills to your health insurance.

What is fever therapy?

Fever therapy activates the immune system in a very natural way. This can be achieved by approved fever-producing substances or by hyperthermia beds through water-filtered infrared-A. The special add-on we provide is checkpoint inhibitors. These have the power to stop cancer’s ability to deceive our immune system. In 2018, the discovery of checkpoint inhibitors was awarded the Nobel prize in medicine.

Contact Information:

Dr. Kleef’s Clinic has moved to Budapest, Hungary.

H-1044, Budapest, Megyeri road 53. MedCity Building.

Timezone: UTC+1 (Winter) UTC +2 (Summer)

Phone: +36 1 615 7555

Please contact us by email for inquiring on therapeutic options:  [email protected]