AstraZeneca PLC (AZN) announced that it has put together a deal with Takeda Pharmaceutical Company Limited (TKPYY) that will see the two collaborate on the development of a brand-new Parkinson's disease asset.

The last week or so has been a busy period for AstraZeneca, with the company announcing the approval of its Faslodex asset as a first-line treatment for women with advanced breast cancer; a deal with German biotechnology company Ethris rooted in a brand-new respiratory disease drug class; and, just yesterday, a collaboration with Boston-based biotechnology company Berg that will investigate the potential use of artificial intelligence (AI) in various neurological diseases.

As such, the latest Takeda deal seems to have gone somewhat unnoticed amid the spectrum of operational developments.

With this in mind, here is a look at the announcement in an attempt to figure out what it means for the companies involved and the Parkinson's disease population long-term.

Before getting started, it's worth noting that Parkinson's disease is one of the most notoriously difficult diseases to treat in the world. Standard of care therapy in the space hasn't really been updated for the past 50 years or so and treatment in question, levodopa, has mixed results that deteriorate over time and in line with disease progression.

It also brings with it a variety of side effects, including the infamous OFF periods that levodopa takers must endure, the latter of which are characterized by serious and often debilitating dyskinesia.

In other words, new treatments are very much needed and many companies have tried and subsequently failed to meet this demand.

The AstraZeneca, Takeda collaboration is rooted in an asset called MEDI1341, which the two companies hope will be able to buck the trend of failure that has plagued the space for decades.

The difficulty with Parkinson's disease is that nobody really knows what causes it. There are some indications that various proteins that build up in the brain might contribute to progression, but – as yet – these proteins have proven to be nothing more than correlative (as opposed to causative). In other words, as Parkinson's disease progresses, certain proteins build up in the brain, but there's no real proof as yet that these proteins that are responsible for the progression.

With MEDI1341, AstraZeneca and Takeda are taking this concept and applying it to a protein called alpha-synuclein, which is found in high levels in the Lewy bodies that form in the nerve cells of Parkinson’s patients.

The drug is designed to both get rid of this protein and inhibit its formation, so the mechanism of action (MOA) is rooted in the idea that by lowering the levels of the protein in the Lewy bodies of Parkinson's disease patients you can either halt the progression of the disease or – even better – reverse it.

Looking at the terms of the deal, AstraZeneca will be responsible for moving the drug into phase 1 development before handing it off to Takeda for continued development once it clears its first hurdle. The latter has committed $400 million to AstraZeneca in development and commercialization capital initially and will share profits on the drug as and when it hits shelves.

It's worth noting that these aren’t the first two companies to go after this protein in a Parkinson's disease indication. Roche Holding AG (RHHBY) has a similar asset, which it is is developing through a partnership with Prothena Corporation plc (PRTA ), in a phase 2 development right now.

However, Roche and Prothena's asset has been shown to interact with the immune system in a way that could potentially cause unwanted side effects. If this is the case, the fact that AstraZeneca is a couple of stages behind Roche along the development pathway for this type of asset isn't too much of a big deal, since the early stage drug could pinch market share from the latter, even if they both get approved, based on an improved tolerability profile.

So what's next?

It's now all about the phase 1 trial that, as mentioned above, AstraZeneca will be responsible for conducting. This trial will establish early-stage safety data and will, with any luck on the part of AstraZeneca shareholders, reinforce the suggestion that the drug can be more tolerable than its competitors.