So far this month, I’ve added two companies to my Stocks and Shares ISA. One is an established FTSE 100 giant, while the other is a newer but surprisingly large Brazilian enterprise.

Bought at $14

First up is Nu Holdings (NYSE: NU), commonly known as Nubank. Despite being largely unknown in the West, this is Latin America’s biggest digital bank with a $75bn market cap.

In fact, it’s the largest online-only bank outside of China and is backed by Warren Buffett!

The share price is up around 90% year to date. And while some investors might baulk at a stock that’s already doing well, there’s a lot to like here, in my opinion.

For starters, the digital lender had 104.5m customers at the end of June. That’s up from 33.3m at the end of 2021 — an astonishing 214% increase. And it currently only operates in three countries — Brazil, Colombia, and Mexico — in a region with approximately 465m adults.

This eye-popping growth highlights how scalable the firm’s low-cost app is compared to bricks-and-mortar competitors. In Q2, revenue jumped 65% year on year to $2.8bn (on a constant-currency basis). Adjusted net income surged 138% to $563m.

Nubank continues to expand its ecosystem beyond savings, loans and insurance. Its Nu Shopping feature, which offers customers discounted access to hundreds of retail partners, is growing rapidly. And it’s just launched a mobile phone service (NuCel) in Brazil.

One risk here is increasing competition, especially from e-commerce and fintech giant MercadoLibre. Also, any sudden slowdown in growth or rise in non-performing loans, could spark a sell-off in the shares.

Looking ahead though, the company appears perfectly positioned to continue growing. According to Latin America Reports, seven in 10 people in the region are unbanked or underbanked. But over 80% now have mobile phones, so this is fertile ground for digital banking and e-commerce growth.

The stock is trading at 26 times forward earnings and five times next year’s sales. A premium yes, but attractive to me given the growth potential.

Bought at £98

The second firm is AstraZeneca (LSE: AZN), in which I recently bought more shares. This followed a 19% drop in the FTSE 100 stock in the space of three weeks.

The reason is China, where its president was detained by authorities last week. This appears related to a large insurance fraud investigation, but we don’t still know exact details.

China is the firm’s second-largest market, contributing 13% of revenue last year. Understandably, the pharma giant is taking these matters “very seriously“. There’s suddenly a lot of uncertainty here.

Looking past this, however, the business is thriving. Today (12 November), it reported that total revenue and core earnings per share (EPS) were up 21% and 27%, respectively, in the third quarter. Both figures beat analysts’ expectations.

CEO Pascal Soriot commented: “Growth looks set to continue through 2025, providing a solid foundation to deliver on our 2030 ambition.” That’s for $80bn in revenue by 2030, up from $45.8bn in 2023.

After this strong performance, Astra now sees high-teens percentage growth in full-year revenue and core EPS, up from a previous forecast of mid-teens growth at constant currency rates.

The stock is 20% cheaper than it was just one month ago. In my eyes, this appears to be a classic buy-the-dip opportunity for me. But only time will tell.