Retisin, Lyastin, Floristen, and Silexil, validated biological formulations that offered help in oncology, inflammation, and regeneration.
Developed by visionary scientists, used by thousands of patients, now revived through cutting-edge science.
A revival of molecules, medicine and legacy of the RNDr. PhMr. Bohumír Rakušan and the RTN Team in Eko company.
This is reInvented Immunology.
What Is RTN and Why It Matters
1940s Origins
Czechoslovak injectable tissue extracts with remarkable regenerative and immune-modulating effects.
Clinical Success
Used in over 12,000 documented cases - treating cancer, gangrene, arthritis, and chronic infections.
The Disappearance
Despite strong clinical outcomes, the therapies vanished - buried by politics, dogma, and complexity.
Modern Revival
Reborn as scientifically validated dietary supplements for longevity, resilience, and cellular health.
The Founder
1919 - EKO
EKO was founded in Prague by Eduard Kolář as a chemical laboratory. He was joined by Dr. Jindřich Křepelka, returning from Harvard. In 1931, upon being named full professor, Křepelka selling his share to Bohumír Rakušan, his assistant at Charles University.
1935 - RTN
RNDr. PhMr. Bohumír Rakušan, a visionary pharmacist. The company was still named "Eko" referring to the name of the founder and embracing the timelessness identity of the company. The death of his brother Jan from leukemia sparked the RTN, a visionary program in tissue-based immunotherapy.
40s - EXPANSION
Numerous advanced RTN compounds have been developed (RTN33, RTN75, RTN102, RTN112, RTN114, RTN118, RTN119, RTN121, RTN122(k), RTN134, RTN140) and registered trademarks of LYASTIN, RETISIN, and SILEXIL. Annual revenue is nearing $40 million USD.
Golden Era of the EKO factory 1935-1948
Clinical Validation
RTN's therapeutic preparations are backed by decades of rigorous clinical testing and institutional validation in Czechoslovakia.
Key Metrics
Patients Studied
Participated in clinical trials, monitored by leading specialists including MUDr. Anna Lundová, Doc. MUDr. Josef Klapetek, Dr. Kroutilová, Dr. Kameníček, MUDr. Karel Bureš, Doc. Dr. Blatný, MUDr. Pavel Pavlovský CSc., MUDr. L. Hanáková, and others.
Years of Research
Dedicated to research and development.
Institutional Partners
Department of Physical Medicine at the Central Military Hospital in Prague
First Gynecology Clinic of Prof. Dr. Klaus
Second Internal Medicine Clinic of Prof. Dr. Vančura
Psychiatric Clinic at the University Hospital in Prague
Oncology Department and Pulmonary Clinic at the University Hospital in Olomouc
Vascular Clinic at the State Therapeutics Institut in Teplice
Institute for the Care of Mother and Child in Prague-Podolí
Robbery
1948 - From pioneer to property of the state
The company was restructured during the second wave of nationalization by the communists, and brought under government control. The RTN project continues under SPOFA as state Factory 15 Eko.
Dr. Rakušan stay as the project leader since the RTN is ready for mass production.
50s - Providing the proven
The RTN transitions into a new phase with the founding of the Institute for Medicinal Plant Research.
Even as the state restructured the pharmaceutical sector, the original RTN team continue in their work.
60s - When ideas saved lives
RTN preparations were officially approved for industrial production, formulated for intramuscular administration.
Retisin, Lyastin, Floristen, and Silexil successfully completed clinical trials and entered large-scale manufacturing, intended as standard tools in national public health.
This wasn’t experimental anymore. It was medicine. Mass-produced. State-approved. Injected across the country. No side effects. No toxicity.
70s - How we killed our own legacy
RTN preparations are quietly shelved, despite clinical success, public support, and physician advocacy. A new wave of pharmacology prefer synthetics - cleaner on paper, simpler to patent, easier to mass-produce.
Standardization wins. We all loses.
80s - Echoes
Long after Retisin vanished from hospitals, two of its original architects, Dr. Bedřich Doležel and MUDr. Gabriel Urbánek, refused to let it die. They patented a method for producing tissue-based preparations under the University of Chemistry and Technology in Prague. The result was a civilian echo of the original Retisin. Dietary supplement named Juvenil, later Imuregen, was manufactured in partnership with the state-run Jednota Hronov collective.
The Velvet Revolution of 1989 brought freedom, and quietly ended the last breath of the RTN.
"New Age"
90s - The Derivatives in commerce
Dr. Bedřich Doležel remained at the university. Jednota Hronov, once a state-run manufacturing collective, slipped into private hands and despite nearing bankruptcy.
Two of his younger academic colleagues saw opportunity and founded Juwima, later branded Juwital and Juwim. Around the same time, Bob Rakušan, son of Dr. Bohumír Rakušan, tried to resurrect his father’s original RTN formulas with their help. But recreating RTN wasn’t like spinning up another supplement. Juvenil/Imuregen aka Juwim lived on. RTN did not.
The former State Glass Research Institute (SVÚS, now part of Nuraxpharm Group), once responsible for producing Imuregen colony under Dr. Doležel’s supervision for Jednota Hronov began using Juwim in a new product called Preventan. They launched their own brand ProteQuine later.
All of these commercial spin-offs retained the fingerprint of Dr. Rakušan.
00s - In the Orbit of Giants
Bob Rakušan, continued experimental work on semi-original derivatives through testing in collaboration with world-renowned chemist Prof. RNDr. Antonín Holý, DrSc., at the IOCB Prague. But the idea remained just that, an idea, until it faded along with Dr. Holý’s passing.
10s - The turn toward longevity
We assemble a new multidisciplinary international team - technologists, doctors and scientists with one goal, validate historical information and transfer them regarding the requirements of the modern world.
Legal Information
Company Registration
RTN Therapeutics s.r.o. | ID: 17380723
Řetouň 66, 400 02 Malečov, Czech Republic
Registered with Regional Court in Ústí nad Labem, File No. C 49191
Trademarks
RTN®, Retisin®, Lyastin®, Floristen®, and Silexil® are registered trademarks of EkoRTN s.r.o.
Licensing
RTN Therapeutics holds exclusive license for production and distribution of all RTN program outcomes.
© 2022–2025. All rights reserved. All other trademarks mentioned are property of their respective owners.
RTN Preparations