Shares of Hikma Pharmaceuticals (LSE: HIK) fell by 13% to around 2,300p this morning, after the group sneaked out a serious profit warning after the market closed on Wednesday night.

Sales from Hikma’s generics division were below expectations during the first half of the year. Although full-year generics revenue is still expected to be within previous guidance of $640m-$670m, profits will be substantially lower.

Hikma said on Wednesday that core operating profit from Generics for the full year is now expected to be $30m-$40m. This implies a core operating margin of about 5%.

The firm’s previous guidance in May was for a core operating margin “in the low double-digits”. Based on last year’s core operating profit of $409m, my calculations suggest this means Hikma’s core operating profit will fall by about 10% this year.

I expect analysts to reduce their full-year forecasts based on this new guidance. With the shares trading on about 26 times earnings, Hikma looks a little too expensive for me.

A 74% profit drop looks bad

Adjusted pre-tax profits at mechanical parts group Brammer (LSE: BRAM) fell by 65% to £5m during the first half of 2016. The slump in profits came despite sales remaining almost unchanged, at £372.3m.

Brammer shares only fell by around 6% following today’s results. Most of the bad news was already in the price after June’s profit warning, which triggered a stunning 56% collapse. Indeed, since hitting a low of 57p at the end of June, Brammer shares have climbed 40% to 87p.

Brammer’s rapid expansion seems to have coincided with falling sales. The firm said this morning that sales per working day fell by 3% during the first half of the year. Sales in the Nordic region and the UK were hardest hit, thanks to the oil market downturn.

The company is now dangerously close to breaching its lending covenants and has suspended dividend payments. Stock levels are being reduced to generate cash and the group’s new chief executive, Meinie Oldersma, is leading a strategic review.

Although Brammer could be an interesting turnaround, I suspect a rights issue may be necessary to reduce debt. I plan to wait for further news before considering an investment.

Another oil casualty?

Consulting firm RPS Group (LSE: RPS) works with customers in the construction, energy and environmental sectors, but the oil market is a key element of the mix.

RPS shares fell by 8% this morning after the firm said that adjusted pre-tax profits fell by 29% to £20.2m during the first half of the year. The firm said it would freeze the interim dividend at 4.66p and would adopt a more cautious approach to acquisitions until conditions improve.

The group’s energy business slumped to a loss of £0.9m during the first half of this year, compared to a profit of £9.6m in 2015. Rising profits elsewhere in the business weren’t enough to offset this big fall.

Acquisition activity meant that net debt rose from £79m to £95m. Although RPS has plenty of headroom left on its lending facilities, this does concern me. With the shares trading on around 14 times forecast earnings and the 5% dividend yield under pressure, I think it’s too soon to buy.

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Roland Head has no position in any shares mentioned. The Motley Fool UK has recommended Hikma Pharmaceuticals. We Fools don't all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors.