Michael J. Fox and Parkinson’s: does the adaptive brain stimulation approved in the US exist in Brazil?

By Ramon Martins Andrade, attorney (OAB/RJ 188.374)

English translation of an article first published in Portuguese: read the original.

Michael J. Fox was 29 when a neurologist told him, in 1991, that the tremor in his little finger was young-onset Parkinson’s disease. In 1998, according to the foundation that bears his name, he “revealed his diagnosis to the press and the public at large”, and in the autumn of 2000 he created the Michael J. Fox Foundation for Parkinson’s Research, which states that it has funded more than three billion dollars in research. On 30 April 2023, two weeks before the premiere of the documentary Still, he told Jane Pauley on CBS Sunday Morning: “It’s getting harder, it’s getting tougher, every day it’s tougher, but that’s the way it is”, and “I’m not gonna be 80”. On 4 January 2025 he received from the Presidency of the United States the Medal of Freedom, the highest American civilian honour, with the citation of “world-renowned advocate for Parkinson’s disease research and development”. The public account ends there: nothing is known, and nothing is stated here, about the doctors, the treatments or the devices he uses or may have used.

Seven weeks after the medal, on 20 February 2025, the FDA, the American health regulator, approved for Medtronic’s deep brain stimulation system “a new optional programming feature called adaptive deep brain stimulation”. The two dates do not touch, but the coincidence produced, in Brazil, a question that reaches the firm with increasing frequency: if the technology was approved there, do the health plan or the SUS (Brazil’s public health system) have to pay for it here? The article answers in layers: what science knows; what a regulatory approval says and what it does not say; how other countries separate the licence to sell from funding; and how Brazilian law, from Lei 6.360/1976 to ADI 7.265, organizes the same separation.

What science knows: the disease, the surgery and the adaptive feature

The World Health Organization estimated, in 2019, “more than 8.5 million” people with Parkinson’s disease worldwide, 329,000 deaths in the year and 5.8 million disability-adjusted life years, “an increase of 81% since 2000”; the prevalence, says the 2023 fact sheet, “has doubled in the past 25 years”. In Brazil, the first calculation with a national sample came out in 2025: from the ELSI-Brasil cohort, Schlickmann and colleagues (Lancet Regional Health Americas, 2025) found a prevalence of 0.84% among people aged 50 or over, from 0.39% in the 50-to-59 age group to 2.75% above 80, and projected that cases would rise from around 536,000 in 2024 to 1.25 million in 2060, with “underdiagnosis in the early stages” and a need for “better access to neurologists”.

Deep brain stimulation, or DBS, is established surgery for the phase of motor fluctuations that medication does not control. The trial that fixed the moment to indicate it, EARLYSTIM, and the criteria of the utilization guideline of the ANS (the health-plan regulator) are in the neighbouring article, on the brain pacemaker denied by the health plan (in Portuguese), and will not be repeated. What matters here is what the “adaptive” feature adds and with what evidence. In conventional DBS, the team fixes the amplitude of the current and readjusts it at consultations. In adaptive DBS, the generator itself reads, through the implanted electrodes, the local electrical activity, the field potentials in the 8-to-30 Hz band, and varies the amplitude within limits set by the physician. The proof of concept comes from Little and colleagues (Annals of Neurology, 2013): in eight patients with advanced disease, stimulation guided by the brain signal improved motor scores by 50% on blinded assessment, 27% more than continuous stimulation, with 56% less stimulation time.

The trial that supported the American approval is ADAPT-PD (Bronte-Stewart and colleagues, JAMA Neurology, 2025), international, open-label, sponsored by the manufacturer, with 68 participants already stable on continuous DBS. The primary endpoint required that at least half of the participants maintain, in the symptom diary, “on” time without troublesome dyskinesia; the target was met by 91% in dual-threshold mode and 79% in single-threshold mode, and the latter reduced the energy delivered by 15%. The authors conclude that long-term adaptive stimulation “was tolerable, effective, and safe” in that population. The FDA’s own Summary of Safety and Effectiveness Data adds what the paper does not say in its abstract: 85 people were enrolled at ten centres, seven of them American; 78.8% had at least one adverse event and 17.6% a serious event; falls were the most common event, in 40%; there was one death, assessed as unrelated to the device; and the success threshold of the primary endpoint was revised after data collection, which, in the agency’s words, precluded formal statistical inference. The adaptive feature, in short, is a plausible and already approved evolution, not a step change proven in a large randomized trial.

The most relevant Brazilian data predate the new feature. The cohort of the Hospital de Clínicas de Porto Alegre (Sánchez-León and colleagues, Arquivos de Neuro-Psiquiatria, 2026), with 101 patients operated on through the SUS between 2012 and 2024, measured the mean ages at each stage: symptom onset at 43.1 years, diagnosis at 45.7, surgical indication at 54.5 and surgery at 56.7; the disease was 10.9 years old when the patient was operated on, and serious complications occurred in 6.9%. The authors point to “delays in surgery, limited access through the public system and problems with device availability”. In Brazil, the question about the adaptive version arrives in a system where the conventional version is still waiting.

What the FDA approved, and what an approval does not say

The American act is a supplement (S478) to the original premarket approval P960009, for the Activa, Percept and SenSight system, granted on 20 February 2025 by an FDA letter to the manufacturer. The letter describes its subject as “a new optional programming feature called adaptive deep brain stimulation”, keeps the indication for use, bilateral stimulation of the internal globus pallidus or the subthalamic nucleus “as an adjunctive therapy in reducing some of the symptoms” of people with levodopa-responsive Parkinson’s, with at least four years of disease and symptoms not controlled by medication, and imposes the usual conditions: sale by prescription, approved labelling and a new supplement for any change affecting safety or effectiveness, with no post-approval study. The technical summary says that the feature “is intended to be an optional tool for the clinician to use” and that the physician sets the amplitude limits.

That is the entire content of a regulatory approval: the product, with that feature and that indication, may be marketed. It does not say that the product must be paid for by anyone. The United States itself draws the distinction in two acts. Medicare coverage comes from a national coverage determination, NCD 160.24, in force since 1 April 2003, which considers DBS “reasonable and necessary” only with “FDA approved devices” and, in addition, requires criteria of its own: at least two cardinal signs, advanced idiopathic disease, “levodopa responsive with clearly defined ‘on’ periods”, disabling symptoms despite optimal therapy and a movement-disorder neurologist in selection and follow-up. FDA approval is a necessary condition of coverage, never a sufficient one. The firm followed the same reasoning when dealing with CAR-T therapy denied by the health plan (in Portuguese).

Comparative law: four systems, the same separation

The examples below were read in the official sources and show different routes to the same separation: in all of them, a software feature that drives an implant is treated as part of the implant.

1. European Union and Germany: CE marking opens the market, the insurer decides afterwards

Regulation (EU) 2017/745, the MDR, defines a medical device as “any instrument, apparatus, appliance, software, implant” intended for medical purposes (art. 2(1)) and admits to the market only a device that complies with the regulation “when duly supplied and properly installed, maintained and used” (art. 5(1)). In Annex VIII, active implantable devices “are classified as class III”, the highest-risk class (rule 8), and “software, which drives a device or influences the use of a device, shall fall within the same class as the device” (point 3.3). The adaptive feature, for that reason, is not a separate app: it is a modification of a class III implant. That is how the manufacturer announced, on 13 January 2025, CE marking for the European Union and the United Kingdom, with the first programming carried out the same day in Amsterdam. CE marking, however, pays for nothing: reimbursement is a matter for each State. In Germany, the Social Code (SGB V) resolves the transition with two rules. Under § 137c, para. 3, methods on which the Federal Joint Committee has not yet decided “may be applied in the context of hospital treatment and claimed by the insured” when they offer “the potential of a necessary treatment alternative”; and, under § 137h, when a hospital applies for the first time for special remuneration for a new method based on a medical device, the application includes “the data on the clinical benefit of the device and complete data on the clinical studies” and, if the method has “a new theoretical-scientific concept”, the Committee assesses, within three months, whether the benefit is proven, whether there is potential or whether the method “is to be regarded as harmful or ineffective”. The German route, in short: the hospital may use it, but the one who pays is the one who assesses.

2. England: a commissioning policy with numerical criteria

In England, the surgery is commissioned nationally under Clinical Commissioning Policy NHSCB/D03/P/b, of April 2013, which defines who is eligible: “life expectancy of 5 years or more”, more than 30% of a 24-hour period in a disabling “off” state or with disabling dyskinesia, “levodopa response of 40% improvement or more” in the motor part of the scale and no significant cognitive impairment. The policy says that DBS “should only be performed in experienced specialist centres willing to publish their outcomes”, records that the stimulator is paid for separately by the commissioner and specifies neither make nor model: it defines the indication and the service, and leaves the technology to the centre. The NICE guideline (NG71, 2017) completes the picture: “Do not offer deep brain stimulation to people with Parkinson’s disease whose symptoms are adequately controlled by best medical therapy”. A new feature enters that design through the door of the specialist centre, not through a new coverage rule.

3. Australia: a Medicare item for each service, including remote programming

The Australian health regulator (TGA) has applied, since 25 February 2021, “new classification rules for programmed and programmable medical devices”. Payment for the medical service comes from Medicare, by numbered item: item 40850 describes “deep brain stimulation (unilateral), functional stereotactic procedure” and admits it, in Parkinson’s, only when “the patient’s response to medical therapy is not sustained” and there are “unacceptable motor fluctuations”. And a new feature gets an item of its own after economic assessment: on 1 November 2022, item 40863 came into force, “electronic analysis and remote programming of the pulse generator”, limited to eight times in twelve months, with a fee of 200.55 Australian dollars, after the Medical Services Advisory Committee (MSAC) recommended its listing in September 2021.

Brazil, first layer: what Anvisa registers

Lei 6.360/1976 (the law on products subject to health surveillance) states, in art. 12, that no product subject to health surveillance, “including imported ones”, may be “manufactured, offered for sale or delivered for consumption before being registered”. The operational rule is RDC Anvisa 751/2022, a resolution of Anvisa (the Brazilian health regulator), which divides devices into four risk classes (art. 5), subjects classes III and IV to registration (art. 7) and, in rule 8 of Annex I, places “active implantable devices or their accessories” in class IV, the maximum-risk class. Two provisions decide the case of the adaptive feature. Art. 8, § 3: “Software that drives a device or influences its use is classified in the same class as that device”. And the definition of software as a medical device (art. 4, XLIII, “d”): “software is not considered SaMD if its purpose is to control the hardware of a medical device”. The adaptive feature, therefore, has no registration of its own: it is an amendment to the registration of the class IV implantable system, and an amendment “requiring approval” takes effect only “after the final decision is published in the Diário Oficial da União” (the Official Gazette) (arts. 4, V, and 21).

The practical consequence is simple to state and laborious to verify. The DBS system has been registered in Brazil for years; the question is whether the registered version of the generator and the software, on the date of the request, includes the adaptive mode with the corresponding indication. The answer lies in Anvisa’s public search of health products and in the instructions for use attached to the registration, not in the American news. The firm tried to run that search in automated form and could not, because the portal requires anti-robot verification at every search. Let it be said in so many words: the Brazilian registration of the adaptive feature was not checked here, and anyone who intends to request it should obtain from the manufacturer or the hospital the registration number, the model and the software version, and check in Anvisa’s search whether the feature is listed.

Second layer: the SUS, the 2025 protocol and the procedure table

In the SUS, Lei 8.080/1990 (the Organic Health Law) organizes the separation in two articles inserted by Lei 12.401/2011. Art. 19-Q assigns to the Ministry of Health, advised by Conitec (the national health-technology assessment committee), the incorporation of “new medicines, products and procedures”, and requires the report to consider the evidence of efficacy and safety and “the comparative economic assessment of the benefits and costs in relation to the technologies already incorporated” (§ 2). Art. 19-T prohibits, at every level of the SUS, payment for “an experimental clinical or surgical procedure, or one whose use is not authorized” by Anvisa, and the “reimbursement of medicines and products, domestic or imported, without registration with Anvisa”. Registration is the floor; incorporation is the door.

DBS has already passed through the door. The protocol in force is the one approved by Joint Ordinance SAES/SECTICS No. 16 of 1 August 2025, which revoked the 2017 protocol and is based on Conitec Recommendation Report No. 957/2024. The text directs that surgery “should be considered” for those for whom “drug treatment has not brought adequate control of motor symptoms”, with the aims of “reducing the intensity of OFF periods, increasing ON time, reducing dyskinesias”, and recalls that “it is not curative and does not halt the progression of the disease”. The candidacy criteria are cumulative: established diagnosis, disabling motor complications not controlled, levodopa-responsive symptoms (except for predominant tremor), “five years of disease evolution”, expected improvement in tremor, bradykinesia and rigidity and, the criterion least read and most important for the new feature, “ease of access to the centre so that periodic adjustments can be made to the programming of the stimulator”. The ordinance requires, in art. 2, that the patient be made aware of risks and adverse effects, and the protocol does not distinguish between stimulation modes: it speaks of a “deep brain stimulator”, and programming is the centre’s task.

In the SUS procedure table the procedures exist with a code and a value, and the opinions of the technical support units that advise the courts (NATJUS) identify them. Technical Note No. 3037/2022 of the NATJUS of the Minas Gerais Court of Justice, on a 69-year-old patient with eleven years of diagnosis and loss of levodopa efficacy, listed, in a search of 22 August 2022, the implantation of an electrode for brain stimulation (04.03.08.001-0, BRL 1,988.31), the implantation of a pulse generator with connector (04.03.08.002-9, BRL 434.80) and the two special materials, totalling BRL 18,523.11, and concluded that the indication “is in line with current technical guidelines” and should be performed “within the window of opportunity”. In Rio de Janeiro, Opinion No. 273/2021 of the federal NATJUS, in a generator-replacement case, confirmed that the replacement “is covered by the SUS” and found in the regulation system a 2018 request carried out by the Instituto do Cérebro Paulo Niemeyer. Neither opinion mentions adaptive mode, a sensing generator or a software version, and the firm found no opinion that does. For the new feature, therefore, there is no table item and no Conitec recommendation among the texts read: there is the prohibition in art. 19-T, which requires registration, and the PCDT, which does not provide for it. The patient’s right, in that scenario, is to the protocol surgery “in due time”, as guaranteed by art. 8 of Lei 15.378/2026 (the Patients’ Rights Statute), and to information, under art. 13 of the same law, on “whether the treatment, the medicine and the diagnostic method are experimental”.

Third layer: the health plan, the ANS list and ADI 7.265

In private health insurance the surgery is on the ANS list of mandatory coverage (the “rol”): Annex I of RN ANS 465/2021 includes the implantation of electrodes and a generator for deep brain stimulation with a utilization guideline, DUT 38, whose five criteria the firm examined sentence by sentence in the neighbouring article (in Portuguese), together with the medical board of RN 424/2017 and the written denial of art. 14 of RN 623/2024; what a utilization guideline is can be found in the text on the DUT (in Portuguese). Art. 8, III, of RN 465 guarantees, in covered procedures, “materials, contrast media, medicines and other supplies necessary for their performance, provided that they are regularized and/or registered and their indications appear in the package insert/manual before ANVISA”. And art. 17, sole paragraph, I, “a”, allows the exclusion of experimental treatment, defined as that which “employs medicines, health products or techniques not registered/not regularized in the country”. Read together: if the generator registered in Brazil, in the version implanted, carries the adaptive mode in the instructions for use approved by Anvisa, the mode is part of the material of the covered procedure, and it is hard to sustain coverage of the generator with the exclusion of one of its functions; if the registered version does not carry it, exclusion as experimental treatment is authorized by the resolution itself, and the discussion ceases to be one of coverage and becomes one of registration.

There remains the possibility of requesting it outside the list. Lei 9.656/1998 (the Health Plans Act) limits mandatory coverage, in art. 10, head provision, to procedures “performed exclusively in Brazil”, makes the list “the basic reference” (§ 12) and, in § 13, inserted by Lei 14.454/2022, directs that what is not listed be authorized when “there is proof of efficacy, in the light of the health sciences, based on scientific evidence and a therapeutic plan” or a recommendation from Conitec or from a renowned international health-technology assessment body, “provided that they are also approved for its own nationals”. The STF (Supreme Federal Court) ruled on that paragraph in ADI 7.265 on 18 September 2025, by seven votes to four, with Justice Luís Roberto Barroso writing the leading opinion, and the court’s official news item summarizes the five cumulative criteria: prescription by the treating physician or dentist; a treatment that “cannot have been expressly denied by the ANS nor be pending analysis for inclusion in the list”; absence of “an adequate therapeutic alternative on the ANS list”; “scientific proof of efficacy and safety”; and “the treatment must be registered with the National Health Surveillance Agency (Anvisa)”. Applied to the adaptive feature, the criteria close in a chain: FDA approval is American registration, not Brazilian, and is not a recommendation from a technology-assessment agency; the list already has a therapeutic alternative, which is conventional DBS; and, without Anvisa registration, the fifth criterion fails before the others. The FDA appears in none of the five.

The rights that Brazilian law already gives to people with Parkinson’s

While the new feature has no route, the disease has rights in writing. Lei 7.713/1988 (the income-tax law), in art. 6, XIV, exempts from income tax “retirement or reserve pay” received by people with “Parkinson’s disease”, “on the basis of a finding by specialized medicine, even if the disease was contracted after retirement or reserve”. Lei 8.213/1991 (the Social Security Benefits Act), in art. 151, as worded by Lei 13.135/2015, waives the qualifying period for disability benefits for the insured person who, after joining, “is affected” by “Parkinson’s disease”, likewise “on the basis of a finding by specialized medicine”. And Lei 15.378/2026 gives the patient information that is “accessible, up to date and sufficient” to decide (art. 12, § 1) and the right to “seek a second opinion or the opinion of another professional or service”, “at any stage of treatment” (art. 18).

On liability, the article is brief because the subject here is access, not error. The hospital and the health-plan operator are strictly liable for the services that are their own (the Código de Defesa do Consumidor, CDC, the Consumer Protection Code, art. 14), and the physician’s liability depends on proof of fault (art. 14, § 4), measured against what the 2025 protocol and the registered instructions for use required at that moment. Anyone who has been operated on and has doubts begins with the medical record, which Lei 15.378/2026 (art. 19) orders to be handed over “without having to give reasons”.

Before deciding

In my view, the most common mistake in this conversation is to treat the FDA news as a right and Anvisa as a rubber stamp. It is the other way round: Brazilian registration is the only door through which the adaptive feature can enter covered surgery, in the SUS under art. 19-T of Lei 8.080 and in the health plan under arts. 8 and 17 of RN 465 and the fifth criterion of ADI 7.265, and not even the courts can supply it, as the Supreme Court held. Anyone with an indication for DBS should, in this order, request the surgery that the protocol and the list already guarantee, with a medical report describing the disease, the response to levodopa and the motor complications; obtain from the centre the model, the registration number and the software version of the proposed system; and only then ask whether the adaptive mode is included in the registered version, because, if it is, it is part of the covered material, and, if it is not, no foreign approval replaces it. If the protocol surgery was denied, if the regulation request has been stalled beyond what the risk classification allows, or if the health plan covered the generator and refused a feature that is in the registered instructions for use, get in touch with the firm: the analysis begins with the device’s regulatory documentation and the team’s report, and does not replace medical assessment.

About the author

Ramon Martins Andrade (OAB/RJ 188.374) is a lawyer who graduated from UFRJ in 2011, with master’s degrees from Université Sorbonne Nouvelle and from the Naval War College (EGN, Brazilian Navy). He is currently a researcher in Human Rights and Health at ENSP/Fiocruz.

This content is for information and education only. It does not constitute legal advice, advertising of results or any guarantee of outcome, under Rule 205/2021 of the Brazilian Bar Association (OAB).