From Consumer App to Enterprise Growth Engine: How Rivia Health Rewrote Its SaaS Playbook to Win Big in Healthcare

When you build a product out of personal frustration, it’s easy to assume the people who share your pain will be your best customers. For Rachel Mertensmeyer, founder and CEO of Rivia Health (formerly RexPay), that starting point was spot-on — but the growth playbook had to change.

Her journey from consumer-focused healthcare app to enterprise SaaS provider offers a masterclass in how buyer intelligence and go-to-market pivots can be the difference between slow traction and scalable growth.

Lesson 1: Start With a Pain You Know Intimately — Then Validate It at Scale

Rachel’s lightbulb moment came after she suffered a severe injury, collecting 38 medical bills from 11 different healthcare systems. She realized:

• 80% of patients feel confused by medical bills.

• Many use credit cards or even tap their 401(k) to pay, unaware that zero-interest plans exist.

• Payment fragmentation creates chaos for patients — and collections nightmares for providers.

Her initial product vision was a TurboTax-style mobile app where patients could snap a picture of a bill, upload it, and pay within minutes. Early user research (200+ patient interviews) confirmed the need.

Buyer intelligence takeaway: Rachel didn’t just build from her own pain — she validated patterns across a large user base, ensuring her MVP would solve problems many buyers shared.

Lesson 2: Your First Customers Might Not Be Your Scalable Market

RexPay launched as a direct-to-consumer solution. Patients loved it. The business model didn’t.

Why?

• SaaS transaction-based revenue needs volume to work.

• Consumer acquisition costs were too high to reach profitability quickly.

Through conversations with experienced SaaS and healthcare advisors, Rachel identified a more scalable route: selling to healthcare providers as enterprise customers.

• Providers could offer Rivia Health’s platform to all their patients at once.

• This immediately unlocked tens or hundreds of thousands of users per deal, without direct CAC.

Sales strategy takeaway: Sometimes the right buyer is upstream — the person who controls access to your end users. Rethinking your go-to-market around that buyer can change the revenue curve overnight.

Lesson 3: Brand Positioning Must Match the Buyer, Not Just the User

RexPay’s original branding — complete with “Rex the Rescue Dog” — was built for anxious patients, making medical billing approachable.

But when the buyer became the VP of Revenue Cycle at a hospital, that playful branding didn’t fit the enterprise procurement process.

• Some deals were lost solely due to “brand mismatch” with hospital systems.

• The rebrand to Rivia Health aligned visuals, messaging, and positioning with enterprise buyers while still supporting a patient-friendly experience.

Marketing takeaway: If your web design, sales deck, or brand voice feels “off” to the person signing the contract, even the best product can stall in the sales cycle.

Lesson 4: In Regulated, High-Stakes Markets, MVP Means “Minimum Viable Compliant Product”

Unlike many SaaS founders who can push out quick, scrappy MVPs, Rachel’s team had to meet strict HIPAA, security, and scalability requirements before launch.

This meant:

• A longer runway to MVP.

• Early prioritization of features tied directly to revenue (i.e., anything that increased bill pay).

• Holding back “nice-to-haves” until core monetization workflows were live.

Product strategy takeaway: In compliance-heavy industries, the “build fast, break things” model fails. The right approach is “build lean, build right” — prioritizing features that prove value to both users and buyers.

Lesson 5: Retention & Revenue Growth Depend on Serving Both Sides of the Market

Rivia Health is now expanding its platform to:

• Enhance the patient-facing experience (faster payments, bill education, insurance integration).

• Add more provider-facing features (automation, analytics, configurability).

Why? In B2B2C models, retention is earned twice — you must keep both the enterprise buyer happy and the end user engaged. Neglect one side, and churn creeps in from the other.

Retention takeaway: Map the buyer journey and the user journey separately. Build features, communications, and success metrics for each — then design marketing and sales enablement around both.

Key Growth Moves from the Rivia Health Playbook

1. Validate with user research — but adapt for buyer realities.

2. Go upstream when CAC sinks growth. Enterprise buyers can deliver scale.

3. Rebrand when your buyer changes. Positioning must match procurement psychology.

4. Prioritize compliant monetization features in regulated markets.

5. Design retention for both buyer and user in B2B2C SaaS.

💡 If your SaaS growth is stalling despite a product users love, the issue may be buyer misalignment, not product-market fit. Rivia Health’s pivot proves that with the right buyer intelligence, brand repositioning, and revenue-focused product strategy, you can turn an acquisition grind into a scalable growth engine.