The $22m is not new funding and comes from a $98m package announced at last year's Budget. It also follows the appointments of a board and chief executives in December.
The funding has been described as "just a start", and will cover current services through Māori health providers through to investment in expanding mātauranga Māori and rongoā services.
Speaking at Takapuwahia Marae in Porirua, hosted by Ngāti Toa, Campbell said it was these Māori-led solutions that had long been ignored by governments yet had previously "allowed Māori to flourish for centuries".
"New Zealand has been dominated by monocultural thinking and approach," he said.
"The system has not worked for Māori for many decades and we have to change it.
"The best work for Māori must come from Māori."
The "best thing" about it was that tangata whenua were willing to share that mātauranga, Campbell said.
"The entire population has the opportunity to benefit from the knowledge and practices of the indigenous people."
Associate Health Minister (Māori) Peeni Henare said the reforms were primarily to fix "a health system that for too long has failed to address the disproportionate health outcomes that Māori face".
"On average, Māori die seven years younger than other population groups. This situation cannot be allowed to continue."
However, a system that worked for Māori worked "better for everyone", he said.
This was illustrated by non-Māori flocking to Māori service providers throughout the pandemic, he said, including Te Whānau o Waipareira Trust which had vaccinated more non-Māori than Māori.
Henare said the initial investment laid the foundation for the authority's role supporting kaupapa Māori health services and expanding te ao Māori solutions across the health system.
"This is about putting whānau first and supporting new and different approaches that work for Māori communities," Henare said.
"I am pleased the interim Māori Health Authority is getting to work quickly to commission providers to deliver services that will make a huge difference for whānau."
Little said the vaccination rollout highlighted the benefits of Māori-led solutions.
Initially the rollout saw Māori vaccinated at about half the rate of non-Māori. This quickly turned around as more resources were provided to Māori providers to lead their own campaigns.
He said these inequities were seen all over the health system, with Māori missing out or only turning up for services when in crisis.
The interim Māori Health Authority will now work with iwi-Māori partnership boards to create services that could include health education, pūrākau, resource development, and models centred on addressing the wider social and environmental determinants of health in their communities.
The authority comes under the Pae Oranga bill, announced in April last year.
Its formation comes after years of outrage from those working in the health sector about inequities and breaches of Te Tiriti o Waitangi, and was recommended by the Waitangi Tribunal in 2019 and the Simpson review last year.
Both Health New Zealand and the Māori Health Authority will become permanent entities in July, and both chief executives will start their new roles in the first quarter.
The reforms have faced heavy scrutiny, particularly the Māori Health Authority which former National leader Judith Collins likened to "separatism". New leader Christopher Luxon has made similar comments.
Little has previously defended functions of the authority, saying it represented partnership, a key principle of the Treaty of Waitangi, and was vital for Māori to turn around hugely inequitable health outcomes, including the fact Māori die on average seven years earlier than non-Māori.
Little said the proposal wasn't for two different systems - but for one system with two partners who will have to agree.
Specific areas that have been identified by the iMHA to be funded include:
$3m for mātauranga Māori (traditional Māori knowledge) initiatives and services.
$6m to support Māori providers with innovation and sustainability.
$5m to support kaupapa Māori approaches to population health.
$2m to expand existing rongoā services.
$2m to support further development of the Māori workforce.
$1.1m to support strengthening national collaboration and sharing exemplar projects.
$3.2m has been allocated by the Māori Health Authority and the Māori Health Directorate of the Ministry of Health to support the establishment of iwi-Māori partnership boards this year.
